Streaming music websites like Grooveshark are great when you're away from home, but they don't have any of your playlists. Free service Groovylists imports your iTunes, Spotify and Last.fm playlists so you can listen to them on other computers.
One of the best parts about the now-defuct streaming service Lala was that you always had your music library wherever you went — no need to sync it between your computers. Grooveshark is still a great service, but leaves you to recreate your library from scratch, including the playlists.
You can't import your entire library into Grooveshark with Groovylists, but you can at least get your favourite playlists from iTunes into your Grooveshark account, which is a huge convenience. All you have to do is export and reupload your iTunes playlist as an XML, copy your Spotify playlist's link, or enter your Last.fm username to get a playlist imported directly into Grooveshark, where you can then copy it to your saved playlists. It's great for folks that use a lot of playlists or have particularly long ones (note, however, that Groovylists will only import a playlist with 200 songs or less). Hit the link to try it out.