need to go here http://www.fallout3nexus.com/ and download some of these fantastic user made Mods...like FOOK etc breathes a ton of new life into the game...Im running FOOK (fallout overhaul kit) and MMM (martigans Mutant Mod) and having a blast with the replay value..
http://www.fallout3nexus.com/downloads/file.php?id=1410 Enclave commander: lets you calll in air strikes or troop reinforcements for the big fights... MMM will give you plenty of those http://www.fallout3nexus.com/downloads/file.php?id=4448 FOOK brings in a crapload of fallout 2 weapons outfits etc...none to overpowered http://www.fallout3nexus.com/downloads/file.php?id=3211 MMM increases the spawn rates and adds a bunch of variety and new creatures top 50 list http://www.fallout3nexus.com/downloads/top.php list of the top 50 :P.