Need a second line? Perhaps you want a number for all those Craigslist ads or for your side project. Regardless of your needs, VoIP.com allows you to add a second line to your mobile phone with their Mobile Line 2 service.
The process seems straightforward, you choose a number you'd like and it is added to your current mobile phone. The line has its own separate voicemail, and allows you to screen your calls while keeping your other phone number private.
The cost? $4.95 per month, plus an additional 2.7 cents per minute rate. You will also need a Blackberry, Windows mobile, or Java-enabled phone in order to run the software.
For more details, check out the Mobile Line 2 site.