It wouldn't be a review/writeup about an old computer if I didn't mention styling, the sunken-in DVD drive is a bit strange but otherwise it's pretty cohesive. Big swamp of grey, it is really grey, I'd say outstandingly grey. It's a pretty simple design, making it look like pretty much every other non-Thinkpad laptop from the 2000s. It's also really big for some reason.
I'd say it's decent, but not super high end. It gets around 1540 points in 3DMark 2001SE. The integrated chipset graphics do leave a lot to be desired unfortunately, since the onboard Intel Extreme Graphics (845GL graphics) aren't great, luckily they don't completely suck.
Yes it runs Linux, I have Arch Linux on mine.
It runs Mac OS X 10.4.8 just fine.
It features an onboard modem, onboard Ethernet, VGA out, Parallel port, PCMCIA slot, CD/DVD combo drive, and 2 USB ports.
Like any good laptop the Acer Travelmate 280 can supposedly be upgraded to 2GB of RAM, mine has 512MB. The CPU uses Socket 478, which means it can supposedly be easily upgraded, however it requires a partial teardown to reach. It also contains a MiniPCI slot for WiFi cards or GPUs if you really wanted.
No