No, I don't mean pretending to be Frugal (you'll need to read everything else I've posted to do that).
It's occurred to me, as things sometimes do, that I talk a little bit too much about miniatures gaming, and not enough about the other, arguably more Frugal kinds of gaming I also do. I'll have to brew up some more stuff on the computer side of things, but for now I want to share a few thoughts about roleplaying.
First thought: roleplaying can be done with precious little stuff. While quite a few modern roleplaying games are either big boxes full of special stuff designed for use with that game and no other (forcing the customer to buy something with only one use), or very obviously built with miniatures and a mat and accessories like that in mind (naming no names), most are not. If you're not into detailed combat-heavy roleplaying and prefer a sort of armchair-improvisational-theatre approach to the business, you can probably get by with books, players and a bag o' generic, not-too-pricey funny-shaped dice.
Second thought: most of any given roleplaying product line is junk. I could go on (and have done, at length, in the past) about how this came to pass, but the short version is that big-name roleplaying game developers have a lot of overheads to cover and they cover them by releasing a steady stream of supplements which, as the game continues to age, contain increasingly irrelevant content. What I've found, as the years have gone by, is that a decent roleplaying game will have a lot of inspiring narrative possibilities implicit in its core rulebook; so many that I frequently want to run two or three games at once so I don't cram all the ideas into one and end up spoiling it. White Wolf are bizarrely good at coming up with interesting and inspiring core manuals that stand up very nicely on their own - I say 'bizzarely' because they're also the dark lords of splatbooking and seem to base their business on releasing a pretty expensive book for every kind of player character, every faction they might join, every location they might visit and so on ad infinitum et nauseam.
Actually, for all that I've had a go at White Wolf, the supplements for their core World of Darkness game tend to be quite good. I've had a lot of mileage out of Antagonists, Mysterious Places and Ghost Stories - the early weeks of my Mage game were essentially a character, location and story hook from each of these books sort of smooshed together, and you could probably run a decent long-term horror game just out of these and the WoD core book.
Third thought: roleplaying has some hidden expenses, not least of which is the cost of feeding four or five visitors to your forbidding doom fortress (hush now Dave, beige walls are VERY forbidding) instead of one or two. Pete did a post on his board gaming night a while back and frankly the same principles apply to roleplaying: if everyone brings food the cost stays down (also you get to sample some fine quality grub, as my Dark Heresy players will attest). I'd mention the time investment here too, but to be honest I'm not sure there's such a massive one. If you're one of those game-runners who insists on having every possible pathway mapped out, every room detailed, every last currency unit assigned to the pocket of an NPC, yeah, it'll take a while. If you cultivate your improvisational skills, you can keep the time investment in a roleplaying game down to the point where it's not much more work than playing a miniatures game once a fortnight would be.
What I look for in a roleplaying game, then, is something that can be run out of one or two core books, that has a lot of replayability (i.e. is flexible enough to tell different stories with and doesn't just fall into predictability the third or fourth time out). What I look for in a supplement is something with more than niche appeal - I'm much more likely to buy a book of generic story hooks than I am a book that details a particular location, or a particular player-character construction option that'll only be useful if someone in the group happens to choose that particular path for their invisible kleptomaniac avatar.
I have a lot of love for Savage Worlds, which is generic enough to run action-heavy games in a lot of different settings, and minimalist enough to allow for stories beyond the pulp adventure stuff that its system is built to facilitate. The core book basically presents you with a wide-open rules system that can fit in anything from robots and spaceships and lasers and stuff to half-orcs and bird-people with honking great swords (and can in fact accommodate both of those in the same game if you're feeling a bit mental), which lends itself to the imaginative campaign designer who doesn't mind doing their own world-building, or who has a background book by someone else lying around to do that bit on their behalf.
In a similar sort of way, Atomic Sock Monkey produce a system called PDQ, which is similarly broad and generic, designed around story-heavy, narrative-driven, lots-of-word-talking gameplay that fits the action in without breaking it up to search for immersion-breaking polyhedra. If your group are quick thinkers with sharp tongues and not afraid to do a bit of describin', I'd recommend this system without a doubt. Oh, and did I mention that it's free? And that the demos for their various settings are also free?
Thought that'd get your interest.