I used to have https://ifttt.com/ set up to send me an SMS whenever a new item was posted to Craigslist that matched my search criteria.  Ifttt.com changed something, because I am no longer getting those alerts, so I found a free/easy alternate to get alerts to my phone right away when someone posts to Craigslist:

  1. Set up a Saved Search in Craigslist and activate alerts to send you an e-mail (in this example, Gmail)
  2. Set up a free pushover account and connect your device to it
  3. Copy the e-mail address Pushover gives you
  4. Create a new filter in Gmail.  “From” should be “alerts@alerts.craigslist.org”, “Subject” should be “alert:”
  5. When prompted, forwarding address should be your pushover e-mail
  6. Be sure to click “Delete” so that the e-mails will get removed from Gmail