I have a client (long time family friend and he even married my best friend's oldest sister) who runs a monument (read: tombstone) company.
Every six months or so, it comes in for a checkover (I make most of my clients do it on a yearly basis for all their machines) and I dismantle everything, pour a small beach worth of very fine sand out of the case, replace the CD-RW, air-blast off (downside up, of course) the motherboard, the cards, et c., replace the fibreglass filters I installed on all the openings, rotate the power supply that I removed and cleaned down to a shine the last time it was in, put it all back together and send it back out to the sand-blasting shop from wence it came.
Repeat.