The great thing about segments is that if you're not from the area, you can spot sections that are possibly worth riding.
When I took my road bike up to scotland in the summer I had a look at strava to try and piece a route together taking in a big hill or two.
Also I like to have a look at the acheivements for each ride, I've got no hope of a KOM round by me (off road anyway) so I can see if different lines/techniques give more speed or not. Even if it's not scientific or accurate you get more of an idea. Most of the time these days though I can go for a lap at cannock and come back with no acheivements at all.