Grew up a console gamer, began switching ot PC ~10 years ago, conversion to PC more or less complete ~6 years ago.
I'm pretty shocked that no one has mentioned Let's Play videos! They're free, and surprisingly satisfying in most cases. I suppose for those into MMOs (not so much for me), but not interested in watching competitive videos, Let's plays may not scratch your itch, but for most other game types, they work pretty well.
I found that for the majority of single player games, especially those that I sort of want to play, but sort of don't want to buy, I'll look on LParchive or youtube for a good player. Like audiobooks, you're subject to the players commentary, so that's sometimes distracting or not so great, but I've probably Let's Played 20-30 games and saved a lot of money by doing so.
Maybe it's not true for everyone, but I get very nearly as much satisfaction from LPs as I do from playing it (except for open world/sandbox types or MMOs, as they'll likely not make the same choices as you would want to). For me, I can't play horror games, but enjoy watching other peoples reaction while they play (See Amnesia), so that opens up a whole new genre for my viewing that I wouldn't otherwise play.
Another benefit is that quite a few of the bigger LP channels on youtube will pick up new releases and start LPing very soon after release.
Some LPs that I rather enjoyed are Amnesia: the dark descent, Dwarf fortress (similar to checking out other people's Minecraft debaucheries), dead space, Bioshock 1, 2, and 3 (I played 1 and 2 before, but LPs give me my nostalgia fix here), Dishonored, assassins creed franchise, Ocarina of time (again for the nostalgia fix), and I
highly, highly recommend Let's Plays of the uncharted series - they play like a movie and are great fun to watch. I enjoyed the Uncharted 2 LP about 98% as much as when I actually played it myself.
Some channels I like are Toegoff, SeaNanners, PewDiePie (I'm not always in the mood for his high energy, but they're usually fairly funny. Highly recommend his Last of Us LP), etc. Check out here for a whole bunch more:
http://letsplay.wikia.com/wiki/List_of_let%27s_playersOther games that can be fun are ones like Impossible Mario for their reaction. These can get old, but are usually good for a quick laugh.