We have a black and grey "Snugli" infant carrier that we are offering for $10. It can be used for infants from 7 to 26 lbs. in the front or on the back (depending on their size). We found it rather comfortable and convenient, and so did our daughter. It's used, but in good condition and clean.

You can pick it up in Menlo Park (close to Santa Cruz Avenue), or I could bring it anywhere on campus.