Oh man, can't decide!
I like the idea behind 1, The before-and-after coin.
I also like the inclusion of BOINC on 2 and 3 since this coin wouldn't be here without it. Between those two, I kinda like the target-feel from the BOINC symbol on coin 3 more than the name on coin 2.
So I'm down to 1 or 3...looks like it ends on eclipse day, so hopefully I'll decide by then!
Voted on 3!