An awesome game concept, great graphics and a brilliant score.
Evil Genius was wat everyone wants: be the bad guy, make tons of money - hell, get your own island, with secret lair and money printing press - and defeat James Bond!
I can go on a very long time, but fact of the matter is that this was one of the last truly inventive games. To bad there never was a sequel.
But what I was thinking, one could make a Tower Defense game out of it...
Build a base, with hallways and rooms. Fill it with traps, just like you could do it with the original game. And watch how the waves of Thieves, Saboteurs, Assassins and Investigators come into your base and try to knock you down!
My view of the game's mechanics:
Attackers
Agents that come into your base with the purpose of defeating you. Get money for destroying them. The higher level unit, the more skilled it is.
Investigators

Killing them will produce little cash.
The higher the agent level, the easier it'll crack your doors and the higher level doors he will be able to crack.

They steal money from the strongroom or special Loot items (achievements of some sort).
Door cracking skills will increase with level also. They can also avoid traps.

Saboteurs
Agents that attack traps and doors. You will need to repair or rebuild the traps if these guy's are finished with them.
The amount of damage increases per level.
The most dangerous of intruders. Their goal is to eliminate you, the Evil Genius!
They skip by lower level doors and traps and will do damage based on their level.

Boss agents
Stronger agent. Can do all of the above. Will get you an awful lot of cash if you kill them!