FUN: Gear you bougth to never use but did use after all.

[FriedMule]

As the title says, have you ever bought a piece of gear that you knew you almost newer would get use for, but in the end used a lot more then then you expected?

[HB9EVI]

not bought but built: DC electronic loads; the very first was just a bunch of 2N3055 with a darlington driver and a pot; since it sucked so much, I built a mcu-controlled one, and right now an even more accurate mcu controlled one is under construction. I simply built and/or tested far more psus than I ever thought

[KL27x]

If you reversed the title, I think you would get more responses.

Good impulse buys I tacked onto a HF order:

1. Having a small corded drill has worked out pretty well for me. I found 90% of the time I used my cordless drill was in the garage, where I have an outlet handy. I haven't used my cordless drill in months. Bonus, the runout on this thing is better than any cordless drill I've ever owned. I dunno what's up with that, but cordless drills seem to be disappointing, in general. This $11.00 made in China corded drill has half the runout of a $150.00 cordless drill that was made in Malaysia. Not as good as my corded drill made in Switzerland, but it's pretty decent at any price.

2. Reciprocating saw. Seems like it would be the last thing I'd ever find useful, seeing as I don't build much of anything bigger than a breadbox. But it is quite handy for clearing out the junk you have been meaning to throw away but have been too lazy to drive it to a dumpster. Where I live, you can't set something out on the curb and expect it to disappear, unless it's actually high value. More likely you'll get a fine from the HOA.  With a sawzall, everything fits in the garbage bin.

[IDEngineer]

* Lambda analog power supply, picked up from a sale of a deceased ham operator's equipment. Figured it might come in handy here and there - now it's the single most used supply on the R&D bench.

* Little (~4 inch) wire enclosed table fan with tilting stand, from the same source. I already had a Boxer fan that I'd wired up with a suicide cord decades ago for dissipating solder fumes, thought I'd maybe formalize that a bit. It's now a permanent fixture on the soldering bench.

And if I might expand your definition a bit, to "Tools you thought you'd use once/for a short time, but ended up being indispensable":

* Case 580SK loader/backhoe, purchased to build a 140ft long x 16ft high  x 6ft thick retaining wall and backfill the ~5000 ft3 of fill behind it, to build a backyard when my son was born. Thought I'd finish that project and sell it. Turns out once you own a loader/backhoe you can never sell it... the projects it makes possible are endless. Since that wall it's helped rebuild a boathouse from the footings up, build a new section of boat dock, build a two-vehicle carport (including acting as a crane to lift the crossbeams), build several boulder retaining walls, cut in a septic system, repave parking areas, keep our neighborhood's system of gravel roads level, and snowplow that same system of gravel roads in the winter (we live at the very end of the road, so guess who is the most motivated to keep the road clear?). Add to that the countless times when neighbors had an emergency and without "the machine" (as we call it) they'd have been forced to call and pay for help. We've pulled RV's out when they've ventured down the wrong too-steep driveway, cut a path for the Post Office vehicles when the other government agency plowed them in, and most recently helped the local church camp fix their water main when it burst several feet underground.

* Hitachi Rotohammer and diamond coring bit, purchased to put a fence on the top of the aforementioned retaining wall. It's amazing how often folks need to cut holes in concrete.

* Lulzbot Mini 3D printer, purchased to expedite the development of a custom injection molded potting enclosure for a PCB. I figured it would gather dust afterwards, but it's since been used to develop an entire second such enclosure too. But probably the most useful application has been the creation of tooling fixtures for use in production of our products. When the Production department needs something to be spaced just so, or held in a certain position, etc. we just crank out a 3D printed jig that holds things in the proper alignment. If they need a dozen (or in one case, 100!) duplicates of such a jig, we just load up the filament and turn it loose knowing every one will be the same. This sort of tool building used to take a lot of time and money, but now it's almost fun to whip up a design, tweak it a bit, and then see the smiles on Production's faces when we make their job SO much easier.

I'm sure there are more, but those are the first that spring to mind. Great idea for a thread!