Hourly Rates:

I'm considering modifying the rates for my computer services.
from lowest hourly rate to highest hourly rate....
Shop rate
On-site rate +20%
If you tried to fix it yourself rate +40%
If it's a Gateway, HP, or Compaq +50%
If it's an e-Machine +75% plus medications and county dump fee
Grumble, grumble.

That reminds me: Black Box - Computer tips for the flummoxed.