That's cool, man. You get 100 style points for using VB6!

I wouldn't spend much more time on this, however.

Even if you upgrade to C/C++ or start experimenting with GPU acceleration, you'll still just be wasting power (average reward per spent energy unit is pitiful, solo mining on a 486 would be more profitable).

Also, the "reward" is immoral, no? What if, by some miracle, you actually find an address with balance? Are you going to keep it? Help yourself to a finder's fee? What if it's someone's life savings?

If I were you, I'd take what I'd learned so far (finite fields, elliptic curves, hashing, etc.) and move on to a more worthwhile project.

Just some unsolicited advice from a fellow programmer, feel free to ignore