I agree, couldn't find a quality image of the MYST book, just delete that one, if I find a better image I will re-upload. The original book would be a natural for the cover . . =)

Just after writing a post about Tex Murphy covers I thought "Why am I asking people to do something if I should be able to do it myself?". So I also did a Tex Murphy Anthology cover, based on Thiev's (I think) Under A Killing Moon cover (as I like his template best) and using some banners from Unofficial Tex Murphy Site. If you like it you can add it to the list ;)
Tex Murphy Anthology cover -> http://img269.imageshack.us/img269/4205/texbp.jpg
And many thanks to Stuff who so quickly responded to my post and did the cover ;)

I approve of your shameless theft, Thiev, I'd have done it myself but you were faster :P
Now, for the covers.
There are still two older Driver: Parallel Lines covers left that are not on your list, Thiev. Click here to see & add them.
And seeing everyone likes packs, I've created a couple of Commandos Collection covers:
Cover 1: http://cubeupload.com/files/634800commandoscollection.png
Cover 2: http://cubeupload.com/files/3ea600commandoscollection.png
Cover 3: http://cubeupload.com/files/961a00commandoscollection.png
Cover 4: http://cubeupload.com/files/dc000commandoscollection.png
I carefully picked up the contrast / hue / saturation levels and made the images generally polished, hopefully you'll like it... I like the first cover the most, the one without any text.

Thiev, please replace the existing Unreal Combo Pack with this one. I had the wrong 2004 cover . . . =)
Unreal Combo Pack : http://www.cubeupload.com/files/4ac600unrealcombopack.jpg

GOG game collection: http://www.cubeupload.com/files/e1d400goggamescollection.jpg
GOG game collection minimal ink usage : http://www.cubeupload.com/files/74aa00goggamescollectionmi.jpg
Mostly for backing up games to a minimum number of disks. Left a space to add a disk number and to list the games on the disk.
Any ideas for improvement appreciated . . .=)
Constructor : http://www.cubeupload.com/files/357e00constructor.jpg
MYST Combo Pack 2 (added URU) : http://www.cubeupload.com/files/36a800mystcombopack2.jpg
MYST URU : http://www.cubeupload.com/files/dab400mysturu.jpg

Neat idea, but is the 'game' part necessary? Considering that GOG = Good Old Games already...

Good point . . .=)
I uploaded the edited files and replaced the links in my post above. Thanks for pointing that out.
Edit: Also added MYST combo pack 2 link with URU added to the mix.
Edit 2: Also added MYST URU, if more than one is submitted use the other since I couldn't find a high quality cover image . . . =)

Arcanum : http://www.cubeupload.com/files/f6f600arcanum.jpg
Gabriel Knight : http://www.cubeupload.com/files/c3b200gabrielknight.jpg
Thiev, if a better cover is submitted, please use it instead of these . . . =)
Edit: Thiev, I usually don't have access to game wallpaper, I purchased this one so . . . I update the Arcanum cover with a much better image . . . thanks . . .=)

Dark Fall Combo Pack : http://www.cubeupload.com/files/1a1200darkfallcombopack.jpg
Dark Fall Lights Out : http://www.cubeupload.com/files/8c6800darkfalllightsout.jpg
Edit : updated file links, removed Activision logo . . .= ^ O . . . seems I'm caught up in the Activision excitement . . .=) . . . sorry Thiev . . . : /

Mob Rule : http://www.cubeupload.com/files/f98800mobrule.jpg

Space Quest 4+5+6 : http://www.cubeupload.com/files/9e2000spacequest456.jpg
Phantasmagoria : http://www.cubeupload.com/files/23c000phantasmagoria.jpg

Caesar III
Cover 1: http://cubeupload.com/files/faa000caesar31.png
Cover 2: http://cubeupload.com/files/9af800caesar32.png

Interstate '76 Arsenal : http://www.cubeupload.com/files/29c600interstate.jpg

Gabriel Knight : The Beast Within A http://www.cubeupload.com/files/9e8a00gabrielknight2a.jpg
Gabriel Knight : The Beast Within B http://www.cubeupload.com/files/b5f800gabrielknight2b.jpg
Kings Quest 4+5+6 : http://www.cubeupload.com/files/8f3600kingsquest456.jpg