The Social Music series is supported by BLive Share, a platform for online music sharing and host of the Groove Armada mini album.

Ah, the perfect playlist. In the quest to find a musical oasis where track after track is a pleasant reprieve from the surrounding world, even the best of efforts are often thwarted by limited song selection, an overly complicated user interface, or the lack of insight into upcoming songs. So we've scoured the web to find only the best musical offerings and we've put together a list of five sites that make playlist building a joy.

You may notice that we've left Pandora and Last.fm off our top 5 list. Although we love each site for separate purposes, they both, in their own way, complicate the process of hand selecting and fine tuning playlists that are musical masterpieces. So don't fret, the 5 sites we've include are bound to help you construct your best online mix yet.

1. Slacker

We recently pitted Slacker against Last.fm in a head to head battle, and even though Slacker fell to a worthier overall opponent, we think it's the top site for building out extensive playlists.

One of Slacker's greatest features is the huge assortment of pre-fabricated stations covering all music genres. Users can take a slacker approach to listening to music by just tuning into one of these stations and loving or banning songs as they go.

When it comes to customizing and creating the perfect station, Slacker is certainly at the head of the class. Custom stations are started with ease — just search for an artist or band — and can be fine-tuned to achieve playlist nirvana. Slacker can recommend related material, and you can add the specific artists or songs you want.

Tired of listening to the same old pop songs? With Slacker you can opt to listen to only fringe or unfamiliar songs, minimize or maximize how frequently your favorites are played, and pick and choose from current or classic artists. Essentially you can build stations from scratch and tweak them to your heart's content. Now that's pretty impressive.

2. Favtape

Favtape, from Ryan Sit and Freestyle Labs, is a mashup of Pandora, Last.fm, SeeqPod, and Slinkset, and it pretty much takes the hassle out of making playlists online. Favtape's tag line claims it's "the easiest way to play music online," though I would argue that it's actually the easiest way to make a fantastic online mixtape.

The playlist creation process comes in two varieties. The simplest way is to create a favtape via search. You can do your own search for a particular artist or song, view the iTunes top 100 songs, flip through the greatest artists by decade, or search by song year. Either way, favtape returns a comprehensive list of songs matching your query that you can listen to, or click to add to a new or existing favtape.

Favtape also plays nicely with both Pandora and Last.fm so you can turn your recent activity — bookmarked, loved, and recent songs — into favtape playlists. Just enter your username for Last.fm, or your profile URL for Pandora, and you'll immediately get an instant song list that you can play with favtape style. Plus you can even find similar artists by song, view lyrics, embed selections on your site, and share across Twitter, Facebook, and Stumbleupon.

3. Blip.fm

Blip.fm isn't your typical playlist builder. The site throws a wrench in the whole music listening experience by going against the grain and automatically creating a playlist based on your friends' blips. It might be a little daunting at first, but once you get the blip of things, your listening experience may never be the same.

Blip centers around you as DJ and the individual songs you blip, so as a user you would search for a track you want to blip, write a Twitter-style note about your selection, and blip it for your listeners. Then, depending on your settings, your blip can be broadcast to social sites like Twitter, FriendFeed, or Tumblr, and even update your Last.fm scrobbler.

As you start to blip a bit more and add favorite friends as DJs, your blip-generated playlist starts to expand. You can customize a few settings, but essentially every time your DJs blip, their songs will be populated in your mix for a potentially never-ending assortment of songs.

Blip.fm offers a handful of additional features like the ability to view and add DJs with similar tastes, and the option to give your favorite DJs kudos. Ultimately we think Blip to be a fantastic way to add variety to otherwise monotonous playlists.

4. 8tracks

8tracks, similar to the semi-defunct Muxtape, takes a fun approach to creating custom mixes with the idea being that user-crafted music programming is more entertaining than algorithm-generated lists — so swapping mixes with friends becomes the central focus of the site.

You can do two things on 8tracks, listen to mixes or create your own, and it's as simple as it sounds. Your 8tracks mixed tape must have — you guessed it — 8 tracks. Users can either upload their own MP3s or browse from the 8tracks library to drag and drop tracks to build mini libraries. Once you've created your playlist you can give it a creative title, write a description, tag it, send it to Twitter, and embed it across the web.

The beauty of 8tracks, however, has less to do with creating your own music combos and more to do with stumbling across fantastic compilations other members have masterminded. Given that you only get 30 second snippets when you listen to your own concoctions, it's probably not the best choice if you want to listen to your music. If, however, you're in the mood to experiment, you'll find some incredibly diverse musical offerings in your mix feed, from the friends you follow, or by experimenting with the popular mix section.

We think 8tracks is a fantastic way to create community around music, and we love that the playlists you build become like custom radio stations for others to enjoy.

5. Grooveshark

Grooveshark's simple and clean user interface is designed for creating playlists, making it a breeze to start a new music mix on the fly. You can quickly search songs, people, genres, albums, and existing playlists to get started, but after your initial query Grooveshark will do the rest of the work for you.

Once you find a song or artist you like, you can start a playlist. Grooveshark will then recommend songs based on your selection, and you can either favorite songs, play the songs, add them to your queue or playlist, or embed them as a widget on your own site. As with most sites these days, you can also share your Grooveshark musical selections with Twitter, Facebook, and Stumbleupon, or grab the RSS feeds of your activity to take with you.

Grooveshark continues to play as you browse for new songs, take a look at popular tracks, build up your queue, or upload your own tracks. Since you have complete control over the songs on your playlist, Grooveshark offers the perfect solution for hassle-free online music streaming without all the guesswork.

The Social Music series is supported by Bacardi BLive Share, a platform for online music sharing. BLive Share members get access to exclusive tracks from the Groove Armada mini album free of charge. Learn more about BLive Share.

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Image courtesy of iStockphoto, chuntise