I read a thread on Big Purple the other day (caution: language NSFW) where a gamer was bemoaning the huge investment he'd made in RPGs over the books without getting any gameplay out of them. I think a lot of us end up in that boat: we get excited over the new hotness, and then it sits. And sits. And sits. It's one of the reasons I've changed my purchasing habits at Gen Con Indy: that which is shiny on the first morning of Gen Con does not necessarily stay as such.
It's one of the reasons I appreciate the efforts of those putting out free games; it really does help when gamers can get their fix and it doesn't cost them $40 a pop. Simply put, though, most of us are to a point in our lives where there's no conceivable way we're going to get through all the gaming material we have, let alone anything else we decide to pick up.
I think that's one of the reasons I plan on sticking with Palladium and Rifts for a good while. I have the core book needed, and it's one of the games I grew up on. It's also easy to introduce multiple themes and genres into, which makes it easier to scratch any itches (supers, horror) that might come along. If I do feel like buying something, Palladium's supplements are cheap (especially on the secondhand market), and generally stay in print. Plus, there's the legendary X-Mas Grab Bag offering (including usually one X-Mas in July sale) that remain one of the best values in gaming.
It's difficult when there are so many amazing people doing great work in RPGs, but for at least a year now, most of my purchases have been dice and game accessories, little things here and there. I'm sure I'm not alone in that. Time to pick a place for a while and settle down for a bit. And if I've got to pick a place, it might as well have a kitchen sink.