FGS, they're a dreadful idea! Don't do it, seriously! Someone will suggest a KAL for a pattern you don't have, but you'll think is really cute and before you know it you've committed yourself to 3 KAL's just for May!
On Ravelry, the Selfish Knitters group are having a KAL called Lace and Flowers - basically we can knit anything lace or anything to do with flowers.
Goddessknits is also starting a KAL soon, I think hers starts on the 17th? I'm not sure without checking.
I've got all those socks I've found and the entire contents of Victorian Lace Today to knit. Sooner or later, I'm going to have to make a start on that wedding ring shawl - yes, it's back on, but he's on probation so there's no definitive date yet. But I'd rather have it done and waiting, rather than be tied to a schedule for it!
There are not enough hours in the day and I obviously need more hands!