The penny-pinching cheapoids at The Simple dollar came up with twenty five gadgets that actually save you money when you use them.
Some may take longer to reach the break-even point than others—like the Toyota Prius and a residential windmill, for example—but a couple of them should see returns in a few weeks.
Some notable examples are the battery charger, the electricity usage monitor, an espresso machine, a coin sorter, and even a laptop. Laptop? Yes, if you're cheap enough that you take your laptop to the library or the book store to siphon off their electricity, you can indeed save money with a laptop.
25 Gadgets That Actually Save Money [The Simple Dollar]