Another of my favotire multiplayer games was The Perfect General on the Amiga (I recall it worked via modem, nullmodem, but not tcp/ip).
As a single player game it's good enough to amuse you for a couple weeks, as a multiplayer game it's still a great game 15 years later.
On an aside note, if you were a fan of TPG there is now a windows based version for Internet play (Bethesda released the source to a fellow). All of the classic sets are available online for $25, includes quite a bit of fan created and supported maps and scenarios (I even did a few under the name of Jagabot). There is also a yahoo group for The Perfect General where people arrange matches and share maps etc. You can also download a demo to try the game before buying it (demo includes a couple maps and it does work online for multiplayer). The same guy makes a new Empire Deluxe which is every bit as good as the original (except it's multiplayer online). Sadly, they're all PC only with the start of Mac support but no Amiga versions forthcoming.
