Re:
If the components your using are all 10/100, and the cards are operating at 100mbps, (megabits) than theoritically intranet bandwidth should be 12.5Mb/s (Megabytes). I find that usually my transfers top out at around 8.5Mb/s, albeit that is usually enough to transfer a full length movie in under a minute.
If your getting 1 megabyte transfer speeds, than your network is running at 10mbps. Find whatever is limiting the network to 10mbps, and fix it.
If everyone is experiencing speeds 10mbps speeds, and you all have 100mbps cards, than the problem is a switch/hub/router.
Inversely, if only one or two are experiencing the lower speeds, and the hub/switch/router is 100mbps, than the problem is a misconfigured card (or the card simply does not support 100mbps.)
-Xtrecate