Kennedy Half "Error" Question

Hi everyone,

I had a question about Kennedy half dollars. I have one or two that are lacking the "FG" initials on the reverse. Are they worth anything? Besides 50 cents? I have never been able to find a really good source of information about these, so I thought i'd ask here. Oh, and is there a market for these coins?

Thanks,
Alex.

I also checked ebay a few minutes ago and there are 3 listed there, but two are slabbed, and one is uncirculated. The other thing was that those are 1982P, but mine is a 1984.

I'll keep it if it's in really good condition. But if not, just let it go. They're more common than one might think.