In reply to The Lemming:
I tend to use a bi-pod (i.e. the wife) if I need something and there isnt a convenient immobile object around.
Ive got a mini tripod that I take with me to balance on walls, rocks etc, Ive also got a large tripod that rarely gets any use other than for long exposure shots, many cameras these days have such good ISO ranges when coupled with a good lens with low Fstop means I dont need a pod.
Ive tried a monopod but found it awkward - unless you can plant it firmly in to soft ground it sways around a fair bit, which will help reduce hand tremor (useful for long heavy lenses?) but thats about it!
Im not a pro photographer btw but I do like to experiment a lot.
edit - I just read the previous replies, all my stuff is covered in there already so, read the above!
Post edited at 09:16