If you're over 28 and your parents had a computer in the house growing up, there's a reasonably good chance you've played some of these.
Because it's now 2016 and copyright law is a mind-bending wormhole of loopholes and who-knows-what, a huge amount of PC games have now become public domain and readily available on the Internet. The Internet Archive, which is a genuinely interesting website if you ever get nostalgic or wonder about what all this looked like, has collected and collated 1,086 games that are now public domain and made them available to play through your browser.
There's a few interesting ones in the list, including Windows Skiing (you'll know it when you see it), a PC version of the boardgame Risk, Wheel of Fortune, BrickBreaker II (that's the one that's a mix of Pong and Tetris) and a few other classics in there as well.
Look, obviously this isn't for everyone, but if you had a dusty old IBM / Packard Bell computer lying up in the attic and you're not arsed climbing up to get at it, this is a neat little trip down memory lane.