Which pc headsets do you use (if any) 
I use a plantronics gamecom.  giant, but pretty comfortable. 
Do you guys even think a headset is worth it for the pc?

I use a Microsoft Lifechat LX-3000. It's OK for the most part, sounds aren't too bad but the bass seems to be a bit on the weak side and the maximum volume is nothing impressive. Obviously, it's not exactly gaming-oriented.
My Logitech speakers sound better so I just keep them as the main sound output and use the mic on the headset. I also have a generic mic hooked up for when I don't feel like using the headset.
Additionally, I'm planning to see if I can get my BT cellphone headset to work with Ventrilo. I should be able to separate the voice chat from the rest of the sounds this way.

I love my Steelseries 5h v2.  I will definitely be buying a Steelseries headset again.

I have a  Byerdynamic DT770 Pro 80Ohm. 
One of the best closed headphones, it has pretty good low and high range...
Low ranges make the explosions feel awesome.
 
And I just got a USB clip-on mic that I attached to the cable of the headphones.

I have Sony MDR-XD200s. They were £20, so they likely are not comparable to some of the stuff others use. But they give great sound quality. Plus they have three modes which don't seem to be any different. For those who know about PC headsets, can you share your opinion of my headset so I know if it's decent or not? I like it a lot personally.

 http://www.ebuyer.com/product/111651
 
Cost me £6. Works well enough for what I need it for.

sennheiser HD650 
 
edit: oh headsets, not headphones :p i need sleep.

Steelseries Siberia v2, definitely better then my old Trittons. I have semi large ears though so they do get a little painful eventually, but thats just my stupid ears.

Astro A40 audio system. 
 
Goddamn they sound good, and people can actually hear me on the mic. (They'd better be good for how much I paid for them).

Currently use Tritton AX720 for the times I have to play something that I don't want the kids to hear, like Fallout 3. Boy, do they swear a lot in that game. Pretty happy with them.

I've got a Logitech 960 USB. Works very well, better and more convenient than text chat in TF2.

" I have a  Byerdynamic DT770 Pro 80Ohm.  One of the best closed headphones, it has pretty good low and high range... Low ranges make the explosions feel awesome. And I just got a USB clip-on mic that I attached to the cable of the headphones. "