I'm up in NH for a week of vacation (not the original plan, but the logistics were easier), and I ended up booking a hotel conveniently located at the base of a mountain that happens to have a lift-supported bike trail network. I've been riding for years, but I've never done this sort of thing, so I figured why not? I mean, what could go wrong?
I should point out that my bikes are, um, experienced. OK, old. This one, an early 90s vintage Giant 780, came out of the dump with a wrecked drivetrain. I stripped it and rebuilt it, either refurbishing or replacing every component as necessary, then shot the frame with some appliance enamel. It's been great for bombing around my local dirt roads and (relatively mild) trails, but this, as it turns out, was different.
I managed to do eight runs in 3.5 hours, running down the easiest flow trails, which didn't feel all that easy to me. I also got a bunch of comments from people about the bike, which can be summed up as either older riders admiring and feeling nostalgic about it, and kids (anyone under 30 at this point) looking mouth agape and saying things like "aw, hell naw". Every other bike on the mountain was a full suspension rig that looked like it came from the future. My bike actually did pretty well, all things considered. It handled everything at reasonable speeds (no one passed me, at least) and never felt like it was holding me back.
If there was a weak point, it was my fleshy pink meatsack. Aside from learning to handle the bike on fast, steep, and twisty trails, I had to contend with levels of abuse I don't normally encounter. When the trails were smooth, everything was good, but hit the rocks or the several washboard sections, and my body was less happy. The rigid bike - in spite of the steel frame and relatively supple tires - did nothing to dampen the significant shocks and vibrations. By the end, I was definitely feeling it, but it was a really fun day, even riding my old junk. Recommended if you've got a similar facility nearby.