Working on KalSMS - an app that lets an Android device function as an SMS gateway: http://github.com/niryariv/KalSMS/wiki

If you live where Twilio/Textmarks/etc already cover, it's just a fun hack, but in developing nations it could be a bigger deal. Current solutions require non-trivial setup (software + cell modem) and NGOs sometimes send technicians for a couple weeks to Africa just to set up the gateway. KalSMS (like any Android app) could be installed by simply scanning a barcode - and maintenance just means keeping the phone on, something non-techies easily do already.

Looking for beta testers, and anyone who might donate/sell me a Nexus One to develop on..