This is one of the reasons why I always recommend running sims/games on a dedicated machine, one that is not regularly exposed to the Internet. Setting up a machine to run performance applications (games) and setting up a machine for office/Internet chores (which requires security) do not mix.
Don't forget more and more games are going heavily online right from the get-go, ESPECIALLY for multi-player mode.
Want some examples? Nearly every single game produced by Blizzard Entertainment has 'local' solo-player, LAN multi-player and Battle.Net, the only 2 games that don't have all three are Original Warcraft (Solo/LAN) & World of Warcraft (pure Battle.Net).
And for those who run games like Star Trek Online, City of Heroes/Villains, World of Warcraft, Second Life, Perfect World, Final Fantasy XI, you NEED a machine with a high-speed (Broadband) connection to the internet just to play them, so putting them on a dedicated machine that rarely hits the net is a waste of time.
Heck, in StarCraft II (currently in Beta, but due out in Aus late-July) you've got solo play, but to LAN for multiplayer, you've got to go through the Battle.Net system to authenticate the fact that your copy of the game is genuine (else, Battle.net is most likely gonna prevent you from getting any further with your 'pirate' copy of SC2), kinda like how XP SP2 brought in WGA which often screwed up and told folks with Valid copies of XP that they were Pirate and needed to be shut down... But that's a story for elsewhere.
Oh! And let's not forget doing things like getting updates for your games or using things such as the Content Manager to download data for your games!
TL;DR - Dedicated gaming machine that rarely (if ever) hits the internet - stupid idea no matter WHO you are!