There's a certain agony associated with searching for travel, some of which a flight-aggregation engine like Kayak alleviates. But what if you could nix the strain of weeding through flights with out-of-the-way or uncomfortably long layovers? Enter Hipmunk. The radically simple flight-and-hotel search site is so user-friendly that it's become a darling of the start-up world. Founded by Steve Huffman, a Reddit founder who programmed much of the site and often answers online help chats himself, along with 23-year-old business whiz-slash-travel expert Adam Goldstein, the site almost can't help but be lovable. It not only curates flights (by hiding about 70 percent of flights, when they're of lesser quality or higher price than other results), but also caters to individual tastes, by allowing users to sort by the qualities of travel most important to them: cost, speed, or simply minimal "agony." Now that's the ticket.

COST: Free.