Ok... You first!
Joke.
My first were some DIY fullrange garbage, pioneer drivers. Who cares.
My second were Hawthorn OB Silver Iris 15"s. I pretty heavily dampened every last bit of them with caulk rope and some putty stuff I can't recall. The crossovers received Obbligato Gold capacitors (they cost almost as much as speakers). But I had to build some subwoofers for under them. I tried some Dynaudio's but they fell on their face in the large boxes required to get them to play low. Then I switched to 12" Dayton DVC's that are a gamble to order. The Dayton's are musical, play low, and in general very good performance. The cabs are tall enough that they're the stands for the Hawthorns. They got me in trouble with a neighbor once. MMC plate amps or something, I forget. Overall it was fun to listen to, but honestly I think the tweeters don't work in a house. There just isn't enough room. The one time they really sang and would impress anyone on this forum was when I used them outside for a Eulogy for my grandfather. In that setting they're freaking awesome. I mean they're literally like hearing a concert (except I never made it to a Frank Sinatra concert). My father has them now, but some day I might have to do an outside session with them again because it's crazy fun. Although subwoofers that could keep up will be tough; skippable though because they play decently low outside.
I've also made some GR-Research Encore X-LS, fully upgraded speakers (made a pair for a friend, so he bought me parts to make some for myself). They are quite good, actually. Sadly so much of Danny's stuff only gets played on mediocre electronics so not every knows; unless they've bought some of the $20k speakers that have won cost no object awards and such.
That's it so far. My time is thinning out that I get to do little projects like this, that aren't in the orientation of products.