So Skarpi, what *did* you tell her? Does you does or does you don't shave sack? :-)
FWIW, trimming the thatch occasionally is a good plan if you're prone to hairyness - minimises overheating in summer, and nicer for your partner. Don't overtrim though. As has previously been pointed out, hair growing back is *very* itchy, quite apart from the "shaved turkey" look.
Paul, re nose hair, I use a disposable razor head (Gillette Sensor) which is just about the right size to go round the inside of a nostril when detached from the razor handle. No need for a fancy trimmer or anything like that. Only two things to be careful of: firstly mind your fingers; and secondly always scrape across the blade, not down it, otherwise you'll have the mother of all nosebleeds. It's certainly a lot safer than scissors though, where one false move puts a sharp pointed implement up your sinuses!
The alternative to trimming nose hair is nasal dreadlocks, which ain't a pretty sight. I knew a bloke whose nose hair reached his top lip - I can't believe his wife wouldn't tell him "that's a bit gross dear, go and have a trim".