When you find the location of the lost hoard of the obelisks, the treasure includes 250,000 gold. Open and close the location or chest it's at before leaving the location and the gold will increase by 250,000 gold pieces every time. Repeat until you have 9,999,999 gold pieces.
NOTE: This trick relies on a bug in version 1.0. It will not work in version 1.1 or later.
Get Weapons, Items, etc.
Some powerful enemies drop high-level items more frequently than others. In particular, Power Liches, Dragons and Veterans will drop an item 30% of the time. Save your game before checking a body and restore if a valuable item doesn't come up on the search.
Tons of Experience
Go to the town of Kriegspire after doing the 9,999,999 gold trick. There is a well in town that takes 5,000 gold but gives 5,000 experience. Use that well over and over again until for each of your characters.
In Bootleg Bay there is a dungeon with a Fire
Lord type of creature. When you clear out the
whole dungeon, go talk to him. You may click QUEST as many times as your heart desires. I got over 4 million experience. You cannot go back to him later and make sure you don't end the conversation until you have as much experience as you want.