1: fruit, 100 per town fruit, 500 per exotic fruit
2: furniture, no a good profit unless you sell rare ones
3: bugs, sometimes makes big bucks, most of the time doesn't.
4: fishes, easy buck, sometimes a pocketfull can worth 10,000
5: stuff of the street: unsanitary, but you can reel some cash in
6: fossils, huge money makers, 3 new things pop up underground every day and might be a fossil, gyroid, or pitfall. That's a good thing for you TTers, you can collect alot.
7: Gyroids: I hate 'em. I dig 'em up, and as soon as I do, i toss it into nook's hands, and grab the money. Never put those almost worthless gyroids in your house, use em for cash.
8: Lost and found stuff: Quick buck, sell it
9: White turnips: Good money, but they don't survive time traveling SO HA-HA TTERS!!! (with an exception to the "table turnips" glitch.)
10: Red turnips: hard to grow, easy to sell, it gets you 16,000
11: your own leg: I"m joking..