Bukkit

VoteCheck - Vote Reward Plugin (Votifier and MinecraftHangout.com)

Require Players to pay to mine

MobCash gives players money when they kill a mob

MagicSigns

Customized TradingCards with Binders!

FC_Bounties

This is an economy plugin. It can be used to trade or etc.

Ultra-Lightweight Money and Item Reward System for PvE and PvP

Floating items that stay put and can't be picked up. Awesome for shops.

The Slot Machine Plugin for All!

A simple way to setup automatic payments and allowances

mobmoney

Trade items using an in game GUI

An economy based upon physical items

Players can limit kinds of item a container can hold

Buy and sell any item with an easy to use clickable GUI.

ItemEnchanting allows the use of a configurable item for enchanting instead of experience.

A plugin that supplies a bunch of essential commands for running a server.

generate regions with just one command!

A very handy tool to dynamically reset mines