Has anyone tried any of this stuff? I've been thinking of trying a toolvest, for what little I carry these days.

Check out the the "Electrician that got mad page" and thier "built in knee pads"
http://www.skillers.com/SkillersWorkwear_OurStory.htm

Called Snickers in the UK! quite expensive but very good quality. Especially good if you can remember which damn pocket out of the hundred you put the gear into in the first place.