Computer clean-up service

In the not too distant past, I used to upgrade my computer every 3 months or so. This forced me to choose between eating once every week and getting a part-time job. Obviously I chose the latter, and started servicing and repairing computers at home.

Once in a while, I would get a customer asking me to clean up the insides of their PC from any dirt that has made the computer tower its permanent home. However, on this particular day, this customer's computer was found to host, quite probably, a bit more than just dirt...