I saw a sha1 contest that will start on next monday and will run for 30 hours.
Too late for me, but as it is relatively simple to do a sha1 hashed password attack with CUDA, I plan to do a little tool for that, just for the fun…
You just have to avoid generating the useless intermediate 2560bits buffer, using 16 internal registers instead + 8 for computing, and as my last post stated it, with macro-threading, you could occupate nearly 100% GPU-cycle of each scalar-processor while checking a global-memory entry that will flag if any thread as found the password.
Will be simpler using macros and manully unlooping the whole process, as the best CPU implementation do! (I think it’s on BSD?)
No thread synchronization (stopping!) needed, no communication penalty, no need to access Shared Memory (anyway coalescing will be easy by nterleaving datas 
)
SHA1 is typically an algorithm that could be ported easily to CUDA!