Watch Dogs, at its best, is a playground for hijinks.
Take for example, an unscripted sequence where I managed to trap a convoy in an intersection by hacking the traffic lights and security pylons, then detonate an entire block with improvised explosive devices, then escape by triggering a blackout of the entire Chicago neighborhood. I felt like a super... well, supervillain, but you get the point.
Of course, most of the abilities described above aren't immediately available. You'll need to unlock them. Here's a quick video guide to enjoying Watch Dogs.