To those wondering what games are "viable" in 2009
PS2 Exclusives that you may want to look into -- most are cheap, too!
the MGS series (the entire Collection can be had for 30 bucks MSRP -- and the Xbox MGS2 sucks)
Ico and Shadow of the Colossus -- while the first may be hard to find, both are amazing
God of War 1/2. I'm not a fan but...
The Silent Hill series. Yea, I know 2 and 4 are on the Xbox -- but 4's Xbox port sucks and 3 is REALLY good.
Onimusha -- Again, theres one of these on the Xbox, but I highly recommend at least the second in the series. It can be had for SUPER cheap, it offers great replay value, and its cheesy in the same way that old school RE games were -- pretty good gameplay, but bad voice acting and translations XD
Zone of the Enders 1 and 2
FFX X-2 and XII
Kingdom Hearts 1 2 and Re:Chain of Memories (Esp. KH2.)
Star Ocean: Till the End of Time
the Xenosaga series (with 3 being the most expensive, but best. And 2 being the cheapest, but "worst")
Persona 3 and 4
Gran Turismo 4
Other games I'd personally look into
Devil May Cry
Shinobi (but not Nightshade)
Radiata Stories
Dark Cloud 1/2
the Shadow Hearts series.
Not to mention the 290834032 "family/casual" games, like Buzz and Singstar. And if you can find the old YDJK PS1 games....the PS2 will play those, too...
Most of thoes games can be had for 20 or less from stores like Gamestop, Walmart, etc.
For $100, that's a DAMN good value. Then again, I LOVE my PS2 and the only reason I jumped to PS3 was because I wanted to get the last model that could play all the old games. In fact, just before this I was playing Xenosaga II XD
There are plenty more good games -- just explore what genres you like best. Chances are, every genre has at least 4 or 5 "good" PS2 games inside of it. Especially RPGs.......