Tabletop roleplaying games are one of the cheapest hobbies around. While the cost is going to be relative to the game you purchase, all you really need are books and dice. The Pathfinder Beginner box will give you everything you need for less than $40. The DCC RPG book is $40, and you can find sets of dice for less than $10. Add another $10 if you want the Zocchi shapes. D&D offers a beginner box for about the same price as the Pathfinder box. The Burning Wheel book is $25. No matter where you start, the cost of entry is not high.
Even better, these games often return huge dividends for these very modest investments. Who can even begin to count the hours they burned slaying Orcs, crawling through muck-filled tubes, or greedily coveting each and every gold piece to fall into their character's hands? There is no /played command for pencil & paper gaming to tell us, but I suspect that those who have stayed with the hobby for a few years have logged the same number of hours that many World of Warcraft players have in that same time period.
I was thinking about all of this as I picked up DCC RPG #71 The 13th Skull at The Compleat Strategist yesterday. Modules are the one thing that don't have quite as high of a return investment, though, again, it really matters what you purchase. A Pathfinder Adventure Path, which consists of 6 softcover books and will give you an entire campaign, are going to set you back $120 and give you roughly 400 pages of material to work through. That might seem like a lot of money, but if you run it as-is, that's a lot of hours of your back as a DM. DCC RPG modules are $10, a little more than the price of three comic books and about thick as one, but each one will give you 1-2 sessions of fun.
I don't have much to offer today. I've just been thinking about how great this hobby is and how consistently I get excited every time it's game night, a cool new book comes out, or one of my players does something inspiring. Cheers.