Ishar: Legend of the Fortress is on GOG as well -- part of the Ishar pack.

Haha. My games research is being shown up for the sloppy work that it was! Thanks for the help mate! Getting closer to that zero mark :)

Both Alien Carnage and Bio Menace are legally free from 3D Realms once you register there.

Well, with luck, one day you'll be able to cross off Day of the Tentacle and Full Throttle, given GOG's LucasArts deal. I'm hoping that day comes along fairly soon, myself! :-)

Yep, they're just teasing us at the moment :)
Interesting! Major Stryker too by the looks. Thanks for the heads up!

And without the songs.

A recap of gratis games:

+ Abuse - Released to public domain in 1997, a truly rare move. Find it here.

+ Death Rally - Windows-only version, unfortunately. Despite what their says, I cannot find it on Joystiq. Isn't Joystiq that recently deceased gaming site? Anyway, you can easily find a working download, and [url=http://community.remedygames.com/showthread.php?t=2618]here is confirmation that it's okay to redistribute the Windows version. Personally, I'd pay for the DOS version, even if this one does work under WINE.

+ Grand Theft Auto - RockStar used to offer GTA, GTA2 and Wild Metal on their Rockstar Classics page, but if you go there now, you'll find it's "unavailable". I have no idea if redistribution is legal, but quick googling shows various large software sites still retain copies of both GTA games. Didn't confirm Wild Metal, though. Edit: I also forgot to mention that GTA is modified for Windows, and they don't ship a DOS executable. This isn't exactly good news for everyone, as it doesn't work under WINE.

+ One Must Fall 2097 - Freeware since 1999. No official page is up, but any abandonware site is fine, as is the open source remake, OpenOMF.

+ Sango Fighter - Official site. Thanks to Foxhack for the info.

+ Stargunner - Find it on GOG or in the 3D Realms game collection below.

+ Arena & Daggerfall - and [url=http://www.elderscrolls.com/daggerfall]here. To their credit or to the credit of whoever maintains their web, these actually work. Take note, Remedy and Rockstar.

+ Various 3D Realms games: Alien Carnage, Bio Menace, Major Stryker, etc. - Available here upon registration. Thanks to Grargar for the info.

+ Blizzard Classics: The Lost Vikings, Blackthorne, Rock 'n' Roll Racing - [url= https://us.battle.net/account/download /?show=classic]This one[/url] is absurdly difficult to find, Blizzard should put aside some of that MMO cash to reorganize their site. They also inexplicably wrapped Blackthorne in a Windows installer, while the other two are just simple zips. And they've modified the game executables. Blackhorne is seemingly unscathed, but their version of The Lost Vikings don't have sound, at least for me. Finally, as already noted in the thread, Rock 'n' Roll Racing is so gimped, it's questionable if it's worth a download. Edit: I've tried fiddling with sound again, and this time I got it to work. Hurray for Timidity! However, the music sounds different in Blizzard's version and my ancient copy. Haven't determined why.

EDIT: Nevermind, need to read things closer.

Awesome summary slide hyper, thank you. The take home message I think is that, whilst there are still many classic games to be added to a site such as GOG, we have access to a great deal many right now. So go forth and enjoy :)

PS. I had a quick go at installing Sango 1 and 2 from that website last night but found the executable files to be a bit buggy. Will try again later.

PPS. OpenOMF looks like it will be a winner when it is released finally!