you can create RSS feeds for any combination of job search query terms & filters at http://simplyhired.com/.

here are a few examples:

Ajax developer:
- http://www.simplyhired.com/r/q_ajax%20developer/mi _25/mr_25/
Java developer, contract only, in San Jose, last 7 days:
- http://www.simplyhired.com/r/q_java/l_san%20jose%2 Cca/cy_SAN%20JOSE/st_CA/z_95150/mi_25/db_7/mr_25/
developers @ Amazon:
- http://www.simplyhired.com/r/q_developer/mi_25/ncn _Amazon.com%2C%20Inc/rl_fortune500companies/mr_25/

you can also slice & dice feeds based on date posted, proximity, ranked list filters, etc.

[full disclosure: i work for SimplyHired.com]