Bukkit is a full update/replacement for your minecraft server.
A straightforward installation, just copy the jar into your server folder.
Take care to backup your world folder in case of loss.
The Bukkit version of the Minecraft server can load plugins just like the original Minecraft server. Just copy plugin files to the plugin folder.
Examples:
worldedit http://dev.bukkit.org/bukkit-plugins/worldedit/
dminigames http://dev.bukkit.org/bukkit-plugins/dminigames/
prophunt http://dev.bukkit.org/bukkit-plugins/tomskiesprophunt/
easy warp http://dev.bukkit.org/bukkit-plugins/easy-warp/
player heads http://dev.bukkit.org/bukkit-plugins/player-heads/
micro blocks http://dev.bukkit.org/bukkit-plugins/microblocks/
commands of interest from the client side:
//hcyl redstainedglass 20 30
/time set 1
//set stonebrick
/clear
/tp selftoplayername
/tp otherplayername toselfname
/me message
/name
/gamemode 1 (sets own gamemode to 1=creative)
/gamemode 0 (sets own gamemode to 0=survival)
/setwarp
/kill
/socialspy
/tell
//walls stonebrick
//set 0
//set wood
//magicpartyarmourhao:pf
/help
/name
/nick
//wand
/op playername
/deop playername
/kick
/ban
/p1
//x-ray
