The example that comes to mind is my iPad. Last month, I was unwilling to buy one. Now that I've been given one, I intend to replace it when it eventually fails (assuming it has a reasonable lifespan, for a portable computer, and quite possibly replace it with a cellular-data one and drop the data plan from my phone, given that the majority of what I've been doing with it has been tethering the thing via wi-fi anyway. I've sent years liking tablet computers and never finding them practical, then Apple comes along and invents a practical one, and it takes me getting handed one to figure out that it's actually quite useful to me.
Kindle 2 was a weird one. At the time I bought it, it was worth the $360. Now, that would be a rather poor purchase, even ignoring the Kindle 3 at $190- which was, incidentally, a good call. The Kindle is in an odd little in-between place: I'm glad to have it and it's worth the money, and yet I wouldn't have bought it had I already had the iPad- nor would that have been wrong, either. The Kindle 3 display is superb, and justifies having the device- something not true for the K2 given an iPad.
Nintendo DSi: Bad call. In the end, it's a worse system than a DS Lite: no GBA game support, worse key feel, and the downloadable content is not good enough to justify the loss. Don't get me wrong, the Art Style games are awesome, but it just isn't, in the end, enough. Worth it since I already have the system, but not worth buying the system for- and in fact nothing is, so I shouldn't have bought it.
GBA SP, Second Edition, years and years past its prime, paying more than its release cost to get one new in box: Absolutely worth it. The screen is up to modern standards, and in a lot of ways, the GBA library is better than the DS library. That said, I'm biased; SNES-era gaming was always my favorite, Super Smash Bros. aside. Worth it even if I still had the DS Lite, for real backwards compatibility. I will always wonder if I'd be as addicted to video games as I am today had I had anything other than Donkey Kong (GB) as my first Nintendo gamer, and Tetris Attack as the second...
IRex iLiad: Fascinating at the time. Horrible by today's standards. Hey, anybody want a Linux e-ink tablet with a Wacom digitizer, cheap-ish? The three-second page flip time is part of why the Kindle 2 felt miraculous in comparison, I think.
I could go on. I kind of don't want to go to the trouble. I just need to improve my gadget evaluation skills.
I've migrated to DreamWidth. The original post is at http://kistaro.dreamwidth.org/468944.html. View comments at http://kistaro.dreamwidth.org/468944.html#comments; go ahead and use OpenID to post your own.