While certain types of permanent graffiti can be a very beautiful addition to an otherwise bland space, much of the time it's unattractive and a pain to remove. Yarn bombing, however, is a completely different story.

Easily removable, yarn bombing focuses less on making a permanent statement and more on lending a sense of warmth to colder spaces.

See also: 25 Scandalous Needlepoints Your Grandma Would Hate

From bike racks to buses, yarn bombers seem to have found a way to add a knit cover to almost any type of outdoor item. Check out 20 of the most impressive, stringy works — they just might inspire you to craft something of your own.

Not Your Grandma's Knitting: 20 Incredible Yarn Bombs

What do you think of this crafty trend? Share with us in the comments.

Image: Flickr, waltarrrrr