Caller ID Faker app. it lets you call any number and put in any number that will show up on their caller ID and it also gives you the option to change your voice to a deep man's voice or an strange woman's voice when they answer. works awesome. fooled quite a few friends with it hahaha
EDIT: Just checked the market, apparently its not available for download from the market anymore. I have it still so if you need it feel free to let me know, I have the free version of the app that I can send to you.
This message has been brought to you by:
-T-mobile Samsung Galaxy S Vibrant Android 2.3.4 rooted running Revolution JVQ Final Rom with the Bullet Kernel Overclocked to 1.2 GHz and some Voodoo to smooth it all over. Meanwhile getting 6.4 Mbps on the KB5 modem
...yup. and now I owe over a hundred dollar fine for flashing a rom while driving
ps. dont hate on the pink