With all the
interest in Sierra games lately, I thought I should mention that the new Scummvm 1.7.0 is great and plays them perfectly. In Linux.
It also (finally) supports the
LucasArts adventures that are available on Steam. That means that it can play them in Linux.
ScummVM is not an emulator, and is therefore better able to resolve platform-related issues such as CPU speed than an emulator like DosBox would be.
I just spent the afternoon using it to play though the VGA version of Space Quest 1, which is notoriously bug-ridden even in the specially configured DosBox that comes with its Windows Steam release. In ScummVM, a couple of cut scenes had stuttering audio, but the game otherwise ran even better than it did when I played it on a P166mmx 20 years ago.