or paint some ascii art version of a classic painting

That should be nice, but it doesn't need to be the classic painting. It can be virtually anything, if it is done good. I like the Original War videos in Soviet campaign, they are made that way
http://www.youtube.com/watch?v=PI9aAN6cnqM - Polish version of the Soviet campaign intro
I personally will appreciate a painting of HoMaM 2 shield logo, the HoMaM 3 shield or the imperial eagle from Warhammer 40k, but the last one should be "overcopyrighted".
And if it was possible, I'd like to own these paintings :P

Cool ideas, I've saved them :)
I think this whole copyrighted thing isn't anything to worry about. If I had some big budget website where I was advertising and stuff like that then maybe I'd run into some trouble. Doing it privately and on such a small scale isn't an issue.
Its like I said, in my local mall, some guy is selling film and video game stills printed onto canvas from a legit stall. I'll bet he doesn't have permission from all those respective publishers and companies.
I am in the middle of another one, I'll post it soon.
I should run a competition.. I'll find a pixel image I could paint, but slowly and randomly fill in each dot and post the progress. People can then guess what its a picture of, the first one to get it right would win the thing. That would be fun.

Dammit. You win.

In that case you can make some Warhammer 40k chapter/unit/clan/whatever insignias too, some examples are attached.

Woohoo! He's my favourite, way cooler than Bob. Baron Von Blubba was a close second. Now if theres any game that deserves a good HD remake, its bubble bobble, you could even do multiplayer over xbox live or psn

There is.

Bloody well better not be japanese only

Just to change the topic, DRAW A CHICKEN! Wait, that's not iconic, unless you played those old Chuckie games http://en.wikipedia.org/wiki/Chuckie_Egg (not related to the films about murderous dolls) and really thought the world of them (being pecked to death by mad, oversized hens did kind of freak me out back then.), or thought that the Chicken kicking in the Fable games was particularly iconic.

Please remember the classic :
Game Over

1. LOAD "*",8,1
2. http://upload.wikimedia.org/wikipedia/en/a/a6/Atari_BattleZone_Screenshot.png

What about a Darwinian (see attached) or something from Defcon (like a nuke launch), they'd be easy to do and are quite iconic. You could also use the Left 4 Dead '4' symbol, Team Fortress 2 logo to go with the other Valve images.

Iconic 'things' ? Can you use sentences ?
Recent "You've exceeded the number of activations for that game. Please contact support."
Older "R: Tape Loading Error"
Timeless "Insert Coin"

If you don't mind the copyright, there is the Steam logo.
Or there is more franchises that you can use like:
Mario
Zelda
Sonic
GTA
Unreal
Nintendo DS
Geometry Wars
Prince of Persia
Any old LucasArts game
WarioWare
Halo
RockBand/Guitar Hero
a DDR arrow
a pixelised beer
Too much stuff to get inspiration from....
I love the Companion Cube and the Sims marker by the way.