i've been thinking that a crossbow could be a neat thing to have. or at least i thought that when i was 10 or so. any reason to own one? or would i be better off learning the traditional bow? when is the crossbow indispensible...if ever?

i have little archery experiece beyond informal stuff as a kid. i used to do well at it in gym class though. is it something that could be self taught?

Crossbows are generally about the same power as a compound bow.  Personally I prefer the traditional bow, but own a crossbow.  Go figure.  

The two major downsides to a crossbow are:
1) short bolts often go into bales up to their fletching or past, requiring frequent re-fletching if you can find the bolt
2) slower rate of fire, 2nd shot etc than a compound bow
3) accelerated string wear

On the pro-crossbow side, we have:
1) optical scopes w trajectory compensation etc are easily attached to most - but this actually doesn't extend the range for a reasonably good archer, in my experience
2) a bolt can be carried ready to fire
3) can be easier to shoot from behind some cover
4) if you get your bolts custom-made, you can often get a two for one deal on the shafts as they are half the lengths of some regular arrows

I think they are just cool...

PA just took them off of the "restricted" weapon list. That just leaves semi-auto rifles (rim-fire/center-fire) and MG's.

You CAN'T use them in bow season, but you CAN use them in other seasons (small-game, big-game) instead of a shotgun of rifle.

Sort of like you can opt for shotgun-slugs/bow instead of a rifle for deer in rifle season.