[stomachmonkey]

Several options.

1) Upgrade the primary WIFI router with a new dual band signal shaping router then distribute WIFI range extenders throughout the house.

2) Take advantage of the coax drops in the house.

If there is already coax in the vicinity of the gaming computer you can drop another MOCA router there and set it up as a bridge. Advantage there is it'll provide both additional WIFI and hard wired ports. If FIOS is available in your area ask your friends / neighbors if they have an extra one laying around or check Craigslist for Actiontec or Motorola MOCA routers.

3) Use the homes electrical wiring and get some Powerline extenders.