How do you deal with incompetent developers who take the glory of work because they are good at talking?

I would but thats a bit drastic. Any other ideas?

We had an employee like that a few years ago, good at talking, but he got nothing actually done. He was fired after about 6 months...so sometimes things just fixes itself :-)

Let the doers take a vacation for a couple of weeks. When they're back, the talkers will be on the way out.

There's a guy here who literally was talking to my boss about a Flux Capacitor and how it gets around the firewall, and he's been coding something to prevent that. Just to make it seem like he was getting work done.

My boss comes over to me and asks why I don't work as hard as him.

My boss is too uncultured for my tastes.

I'm not a PM or team leader but I think it's not so hard to mesure the programmer efficency, either delivers or not.
Now, (for me) talking is an hability. Maybe he should be doing a client side job

@Leningrad Thankfully our bosses are devs too so that kind of bs wouldnt fly in our place. If I was in your place I would simply take your boss by the hand to the guy and ask him to explain again what exactly is what he did. He wouldnt be able to bs his way that way, and if he tries to you can just push him more so that he tangles himself even more. Then the boss will see it :)

Thanks guys for the suggestions. Code reviews sound like a good idea to expose them.