When you know it’s time to use two computers?

I have a SONY digital voice recorder plugged into my USP port. I’m now creating a 900MB+ MPEG file using Pinnacle Studio, and soon will be using Symantec’s WinFax to send some letters.
These processor intensive activities can slow a computer down.
I’ve realized that if I keep doing this, I’m going to have to get two computers. One so I can keep working on email and web sites and the other for processor intensive work.
Do you find yourself in the same position?