A Silly little thing that I didn't see listed but comes in handy for me occasionally...
If you haven't invested in super leaps, super speed or flying and want to get across town quick without being bothered or having to run around building or jump over things, try running on the train tracks...I've found in a couple of cities at least the tracks cut straight across the town...Just start at the train terminal to get on the tracks, then run on the tracks over all obsticles...Nobody (except an occastional train) seems to bother or even notice you up on the tracks...
Like I said, it's a silly little thing, but seems to work well if you are putting off the faster travel modes in luew of more combat/defense skills.