full time server (like the different server/worlds you can play in most MMORPG's (EQ,EQ2,FF-XI,WoW,DDO,SW-G,etc.)
most Peer2Peer multi-player games that i'v played (so maybe not all of them ever made) are fast paced, RTS and FPS mostly.
for something like a text-based mutli-player game, i would think you'd need a server that's always online. use it to store the data (player actions, mail boxes (if players can mail each other) and all that other good stuff). then when a player logs on, it sends all the stored info.
the near-worthless book i spend $50 on for DB has some stuff in about server-based vs. P2P-based game coding.
then again the book also says you save and load arrays with the full dimensions value in the command, so i won't bother looking the MP stuff up atm.
another idea you might look in to so mail; if it's a turn based game atleast. i'v played acouple games of Civ2-4 by emailing "turns" back and forth, same with Steel Panthers: world at war.
hope this gives ya some idea's atleast. good luck
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