A few weeks ago I entered into the Twilio Developer Contest and found out this past week that the project won! Working with Twilio has been a pleasure and they have been very supportive of my efforts. I encourage other developers to try out their API; you can get up and running very quickly.
SingSend Blog Post on Twilio: http://blog.twilio.com/2010/10/singsend-wins-twilio-play-developer-contest.html
This Week’s Developer Contest: http://blog.twilio.com/2010/10/new-developer-contest-twilio-paypalx-ends-october-31.html