Bang for the buck... in order... in my opinion
1. CRT Rear Projection - Not as bright as the others listed below so it isn't always ideal for off axis viewing or very bright rooms, but the image quality is second to none. Requires you to converge it occassionally, which may take 30 minutes every few months to do. No bulbs!
2. LCD & DLP rear projection - BRIGHT! Looks very good but often shows flaws with regular TV viewing. Optomized for HD and DVD viewing really. These are very slim which is nice, but not always important in a room. They have bulbs that will need to be replaced every 1-4 years depending on usage. These bulbs are USER replacable and run $150 - $500.00 depending on manufacturer.
3. CRT tube type television - limited size, outstanding quality. Very few issues, but 34" or so is pretty much the max size.
4. Plasma - At 42" - 60"+ these provide a bright image in larger displays. They seem to range in price from about $1,600.00 for a entry level 42" Samsung or Panasonic all the way up to $10,000+ for the big guns. A nice 42" HD model with cablecard and speakers can be had for about $1,800 for a 853x480 model (EDTV) or about $2,600 for a 1024x768 model (HDTV) Not a bad price for sure.
5. LCD - Much less variety over 40" and a bit of a premium price tag. Generally a slightly lower quality image than plasma, but very close. They have a great selection under 40" though. In a couple of years, they may well be a better value than plasma, but in my opinion they are still a bit more pricey than they should be and the image isn't quite to the level that it could be at.