An HVAC engineer friend of mine once had an emergency callout where the air-con pump had stopped. Knowing the device involved, he hit it with a lump hammer and it started working again.
On presenting the customer with a bill for £100 emergency callout, he was told "we're not paying you £100 for hitting it with a hammer"
He said "OK, let me re-do the bill" and presented them with a bill for "Resolving issue with pump by hitting it with a hammer: f.o.c.; Knowing exactly where and how hard to hit pump to get it working again without causing damage: £100"
They paid.
Biting the hand that feeds IT
