Shopping online is always an adventure. You hope you're getting the best price for your item, but you're never sure without jumping from website to website. Here's one way to get it done right.

InvisibleHand is an online personal shopping assistant. This browser add-on compares prices across dozens of online stores. That includes big names like Best Buy, Amazon and Walmart. You'll also see results from specialty stores.

Simply search for a product on your favorite site. When you reach a specific product page, InvisibleHand jumps into action. A strip at the top of the window will appear. It will show you how much you could save at another store.

Cost: Free

Link: www.getinvisiblehand.com

System: Windows XP, Vista, 7; OS X