@misc{cryptoeprint:2010:077,
author = {Joppe W. Bos and Thorsten Kleinjung and Ruben Niederhagen and Peter Schwabe},
title = {ECC2K-130 on Cell CPUs},
howpublished = {Cryptology ePrint Archive, Report 2010/077},
year = {2010},
note = {\url{http://eprint.iacr.org/}},
}
You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.