I almost always take two cameras with me if I'm planning on taking photos -- a Digital Rebel XT SLR with a 24-105 f/4 zoom and 50mm f/1.4 prime lens, and a little (but full-featured) Powershot S70 point-and shoot-camera. The SLR allows for better quality photos, but I find that I get the best macro shots with the little S70, as you can see below.
I carry two cameras because I never know where I may end up, especially when out for the day or on a trip.
- The SLR works great -- the shutter fires immediately after pressing the release so I don't miss those split-second expression and actions, and I love being able to look through the lens to compose the shot (the live preview displays just can't compete with the full fidelity and sharpness of real light rays). One main drawback is that the camera can be intrusive because it's so big , plus it gets heavy very quickly.
- The little point-and-shoot is far more discreet and works great when I just want to quickly take some photos or don't want to (or can't) carry around all sorts of camera equipment.