We just started using this
http://m.ebay.com/itm/121927230981
It's a bit simplistic, but the kids love scanning their fingerprint. It's quick, easy, and no one can sign in for someone else. (No cheating ha,ha). We call ours BARF. Biometric Attendance Recording Facilitator. The kids also enjoy the name.
No need for a computer just plug it in and download the records on a flash drive. They come out in an excel file.
We haven't used it alot so I'm not sure how well it's really going to work for us, but I'm hopeful.