OK - I'm going to go overall here, since I spend most of my working time at home on the XJ (not enough time/money/mods for trail work - yet...)
1) Not really a tool, but my inverter is probably the most useful. I mean really - I can charge my Makita batteries wherever I am, and how wifty is that?
2) My 3'x3/8" drive ratchet extension. Picked it up for $10, it's already saved me a minimum of 8 hours and severe knuckle wear on a batch of CPS sensors. No arguments here...
3) My Dremel toolkit (starting with three of the tools proper - two corded and one cordless.) It's not anything super-fancy, but it's been just the ticket for small precision jobs. I can knock parts down to .001" with a little time - as long as I'm not working on anything too hard (material) or any pattern that is too exotic or involved.
4) My bench vise. Metal bender, work holder, anvil - not bad for $40 at Home Depot. Ain't the greatest vise going, but it's cheap enough I don't feel bad beating it with a hammer, filing it, grinding on it, or heating it with a torch, either!
5) My workbenches. I could probably park my XJ on one of them without any trouble. I got the plywood from a salvage job I did a few years ago, so I got to build a pair of nice workbenches (with 3/4" ACX tops!) for about $80 the pair. It would have been less, but I added power outlets to the surface and that makes them all the more convenient. I just take them wherever we move and plug them in, and I don't have to look for an outlet when I need one!
I know not all of these are strictly "tools" - but I've always believe that a "tool" is something you use to expand your capabilites. I was taught years ago that "My gun and my knife are only tools" - and I see no reason to change that philosophy...
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