Attacked

Did you achieve anything? Maybe.
Did you get their plates? Yep.
Did you report them for attempted murder at the local police station? Yep.

Job fucking done.
The cops might not do shit, but that fuck head's details are on record so if he does something again to another cyclist, he/she has a prior mark against their name.

Get their plates and report em? Yeah I've done that. That twat is now on record too. Seriously though, you don't know how much of a twat/nutter you're dealing with. If you're happy to take the risk then more power to ya.

Thing is, this is essentially the same as many other civil/criminal problems. As in:

You're on a bus. Some dicks are playing tunes out of their phone and pissing everyone else off. You tell them to turn it off. The possible outcomes are:

a) They turn it off.
b) They ignore you.
c) They get mouthy and tell you to fuck off.
d) They stab you.

Read the news and you will know that the most tragic outcome has happened more than once, so all I'm saying is - is it really worth it?

So to bring it back into context...

You are riding your bike. An arrogant driver cuts across you, almost forcing you off the road. Do you:

a) Do nothing.
b) Take their plates and report them.
c) Give them the finger and scream at them.
d) Take a lock to their window.

If you chose a or b, then likely you got home safe. If you chose c, then one of the following happened:

a) They ignored you.
b) They gave you shit back, but it didn't get too sketchy.
c) They chased you and tried to attack you.

If you chose d then one of the above happened, but you are in any case guilty of criminal damage.

Is it worth it?