SirPrimalform: Without installing Win 3.x? I thought that those games were playable on DOSBox, but only if you installed Windows in it first.
Crosmando: I honestly don't know, but I assume that's how they made it work (I downloaded an install package similar to GOG's for Turbo on an abandonware site), it plays via a DOSBox shortcut same way GOG does it.
Would their be legal problems with GOG hosting a game with Win 3.x installed within a DOSBox setup?
Well for each sold copy, there would have to be a license for Windows 3.1 to operate within that given environment. Microsoft doesn't even really sell 3.1 anymore and I believe the only first-hand legitimate way to get ahold of it is with a special MSDN subscription. GOG from what I've seen hasn't even began to release Microsoft games, so bundling in one of their (abandoned) operating environments is probably not going to be foreseeable.