Just found out about this yesterday, and it wholly reaffirms my love of the big one-day dance festivals (for cost-effectiveness if nothing else).

http://www.parklife.uk.com/

Bands on the lineup that particularly caught my eye:

Friendly Fires
Booka Shade
SMD
Andy C
Kissy Sell Out
Vitalic
Four Tet
Erol Alkan
Errors
We Have Band
High Contrast
DJ Hype

£30 with booking fee! Great stuff!

Anyone got anything to add?