I love the Dreamcast. Still one of my favourite consoles of all time. I've owned them since they were released, but the funny thing is I never intended buying one when I did. A friend kept entering competitions to win games and kept winning the same games over and over, but putting different people's name and address for the winner. So he won again and 3 Dreamcast games arrived in the post one day and I had to play them, so I bought a Dreamcast!
And I never regretted it. It might not have been as popular as the PSX or have as many releases, but the majority of game releases for the DC were very polished and great fun to play.
The DC visuals also had something special about them. A slightly over saturated colour palette and much better texture handling than the PSX at the time, including much better anti-aliasing then even the PS2 could manage to begin with.
It is a shame that some never experienced the DC in its prime. It was an amazing experience back then. As someone mentioned, it was the first truly internet enabled console, with a built in modem out of the box. It was one of the reasons I got the BT evening and weekend dialup unlimited internet service, so I could be online all night and not worry about the call charges racking up.
Best online game had to be Phantasy Star Online v2. Play this game offline these days and you might find it hard to work out what is so special about it. But back then, logged in to the hubs with loads of people online, and with a DC keyboard connected, and you could chat away to others and go adventuring together. It was one of the first MMO style games that really worked, and for some reason that I've never been able to put my finger on, the same game areas and levels played a lot better in multiplayer and were 100 times more enjoyable. I never got bored and going through the same areas over and over. Great times.
Best games on the system? Shenmue 1 and 2 is an epic story and still holds up well today as an Action Adventure. It was also cool how Sega added their old arcade games within the actual arcades you found within the game. And collecting things was a huge part of the whole gameplay.
There were also so nice RPGs, although not enough. And loads of nice SNK 2D fighters, as well as loads of nice 3D fighting games. A lot of the SNK games are US/Jap only releases so you would need to source them. I was lucky to be able to buy the originals from the US at the time.
Overall I've got an original DC games collection of around 160 games, and I think it includes pretty much all of the decent games released for the system. Only a couple I know I'm missing that I really wanted back at the time, but one of those was a 9 part Japanese only RPG series, and as I don't understand Japanese much it would only have ever been for collection reasons and not to play beyond booting up and playing about for a bit.
As a retro system the Dreamcast is definitely worth buying. It is sad to see them selling for so little these days. Such a great system and in my view Segas best. Not in terms of software, but definitely in terms of hardware. The original Xbox owes a lot to the Dreamcast as it was a lot of the things Sega were planning for the Dreamcast sequel, but instead Sega helped M$ develop the Xbox. Especially its network and its gamepad. Ever noticed the similarities with the 2 gamepads?
as my wee room is becoming overcrowded
after reading some of the positive comments in here, may just end up getting one
) was the first console of the PS2s generation, of which the Xbox was released (though a lot later in that generation) although many people make the mistake of comparing it to PS1 since a lot of PS1 games had ports on the DC. The Saturn was Segas gem from the PS1 generation, and thats another story that deserves its own thread 
