Kayak Review

Kayak.com is very helpful for an easy and quick way to search many sites at once. Their site is simple yet has all of the functions and options to create a search according to your needs. I really enjoy their buzz page which lets you search the cheapest, most recent fares that people have booked for certain cities or areas.

The only issue I dislike about Kayak.com is that sometimes I've been able to find a cheaper fare on an airlines direct website so apparently they aren't always able to find the cheapest fare out there anywhere.
Otherwise it is a great source for knowing what is available for flights or other travel services.