If I were going this year, I would definitely check out the most excellent and amusing Frisky & Mannish, who I first saw some while ago at a secret and not-to-be-talked-of event*:
The Pussycat Dolls and Kate Bush renditions are particularly noteworthy. Any act with the balls to combine Girls Aloud with The Wheels On The Bus should be wildly applauded.
This lovely page has details of the Edinburgh gig.
I thank you. Silliness ahoy, Midshipman Banana!
* Which involved bingo. I'm just saying.