Oh wow...where do I start?

Over the past 8-ish years I've built probably close to 200 PCs for myself, clients and for work. In no particular order of importance:
Forgot to switch PS to 220v (at least twice that I can remember) Thankfully they're all automagic these days.
Didn't plug in floppy power backwards, but one pin "to the left". Drive exploded. Little motor parts all over inside case.
Forgot the thermal paste.
Forgot to use screws to secure HD inside cage. HD fell into CPU HSF. Fan not happy.
Forgot to use screws to attach MB to standoffs. MB not happy at ALL.
With beer in hand, leaned over open, running case to get a look at something. Fried everything.
Spilled can of peanuts into case. No damage but messy.
Didn't connect power cables to HDs or CD-Roms...for 10 mins, couldn't figure out why nothing worked.
That's what I remember off the top of my head. :laugh: