Amazon offers the Kingston 120GB HyperX 3K Serial ATA 6Gb/s 2.5" Solid State Drive, model no. SH103S3/120G for $79.99 with free shipping. That's $0.67/GB and tied as the best non-rebate price we've seen for this drive. (It's a current low by $30.) Features include max write speeds of 510MB/sec and max read speeds of 555MB/sec.

Update: This is just the drive, not the kit, as we noted earlier. We regret the error.