Yes, I have few games that *really* take space :
Galaxian3 Theater 6 (6 players)
*DOUBLE* Twin Daytona USA (playing OutRun2) for yes, 4 players!
Darius Burst EX AC : 4 players
Triple screen/xbox360 setup dedicated to Forza 4
Sega G-LOC *DX* playing After Burner Climax
Starblade
Star Fire *cockpit*
...and not so big, but taking space too :
FireFox *cockpit*
Star Wars *cockpit*
Buggy Boy *triple screen*
Guitar Freaks
...
Yes, I still have some space for more, but ... I'm not really looking for anymore so far... I even would prefer to reduce the number of cabinets TBH. Let's say my 'must have' list is now completed, but I still have a 'nice to have/opportunity' list I'm checking from time to time
I'm no more fan of game rooms with so many games that you cannot play them or simply walk between them.