Use Vumber.

For a low monthly fee, you get a real phone number. When someone calls that number, its forwarded to your cell. You get the Caller ID info.

When you make a call from your cell phone, you can use Vumber service again and the receiver sees your vumber assigned number instead of your cell phone.

So you get complete anonymity/safety/privacy and still get to use your cell phone.

Cheers,

I'll second Net10, it seems to work fine.  If you examine the online registration process closely, you will see you do not need to enter personal information.  And, you can use the registration site through an anonymizer (not all sites work well through them, thank you javascript).  Depending on how you value your privacy, this could be an issue.

I also suggest buying an extra card to keep in the glove compartment etc. because the minutes will run out after x number of days (30?).  It'll be nice to have once you get the hankering, but have run out of days.

Rounding out the "they're out to get me" psychosis, leave the phone in a reasonably safe spot, always leave it off unless you're expecting a call, and never use it for non-hobby reasons.  That phone represents a physical barrier between normal-you and hobby-you.  Until legislators decide to let adults act like adults, mind you.