Parallels is pretty great software that lets you easily run Windows apps on Mac OS X. The latest version was just announced and is faster than ever with full 64-bit support, it retails for $79.99 which isn’t a bad price but why pay more when you don’t have to? I like a good deal, so here’s how to get the newest version, Parallels 6, for $20 (well, actually $19.99). This will work until September 30 when the rebate is no longer offered.

Find and buy Parallels 5 for Mac on Amazon for $39.99

for $39.99 Fill out the $20 rebate form from the developer (the rebate code comes with Parallels 5)

Save your Amazon receipt, then register and activate Parallels at https://www.parallels.com/account/

When Parallels 6 is released (September 14), go back to https://www.parallels.com/account/ to access your free upgrade to Parallels 6

That’s all there is to it! This deal works by taking advantage of the Parallels Tech Guarantee, which states that if you buy a qualifying purchase of Parallels 5 after the eligible dates (August 15, 2010), you will get a free upgrade to version 6 when it is released:

Buy a qualifying Parallels Desktop 5 for Mac product from an authorized reseller or from www.parallels.com starting August 15th, 2010 and you will be eligible upgrade to Parallels Desktop 6 for Mac at no additional cost when it becomes available on September 14.

Save your Parallels Desktop 5 for Mac dated sales receipt, register your product and activation key at https://www.parallels.com/account/ and keep your activation key in a safe place. Bookmark this page and come back once Parallels Desktop 6 for Mac has been released in your language.

Great software at a great price, can’t beat that.

Update: This deal is still active, you have until November 30th, 2010 to buy Parallels 5 and then get a free upgrade to Parallels 6. This is a great deal!

Here’s the date range from Parallels:

Customers who bought a retail box or download version of Parallels Desktop 5 for Mac or Parallels Desktop Switch to Mac Edition from an authorized reseller between August 15th, 2010 and November 30th, 2010 need to proactively claim their upgrade directly with Parallels