I bought Uncharted: Drake's Fortune because of its demo. Other than that, I can't remember any other games.

I bet you bought it.  Right? No? Oh. lol

You remeinded me of Ninja Gaiden, except I add the opposite experience (kinda).  Played the demo and loved it, bought it, but I couldn't handle the difficulty of the game, ended up selling it.

All the time, although most of the time a demo just confirms that it's not really my cup of tea.

Bought because of demo:
- Space invaders infinity gene
- Enslaved
- Majin and the forsaken kingdom
- Catherine
- Rayman origins (on to purchase list after demo)

Interested in but not bought because of demo
- Forza 3
- Driver San Francisco
- Limbo
- Minecraft

Didn't help either way
- Forza 4

Games I bought because of the demo :

• inFamous
• Killzone 2
• Yakuza 3

Games I didn't buy because of the demo :

• Bulletstorm
• Dragon Age II
• Lego Harry Potter

Mass Effect 2!!

It was completely out of my radar. But when I played the Demo......OMG! Now it's one of my favs of this Gen.

And this is because i HATE sci-fi settings...it really turns me out. Actually I never saw more than half of a Star Wars movie.

I was put off buying Halo Reach, Mass Effect 2 and Sonic Generations because of the demo.

The Forza 4 demo made me want to buy the game but I haven't picked it up yet, the MGS4 demo was AMAZING but I knew I was going to buy that game anyway.

Yes. I bought Valkyria Chronicles and Mass Effect 2 after enjoying the demos. I also bought Assassin's Creed 2 after using a free one hour trial of the game on PSN (after the PSN outrage when everyone had a free month of PSN+). I did not buy Killzone 3 after playing it's demo though. I thought it sucked.

Ah yes this too!  I played the demo and just did not like it at all, and that is coming from someone that platinumed KZ2

I bought Dragon Quest VIII for the FFXII demo XD. Not what your asking

I didn't initially buy valkyria chronicles because the demo was boring. Pretty but boring. So I put it off until I got it for like 15 dollars used. And I liked it a lot.

I bought FFVIII and FFVII because of the demo, on PC XD.

Sometimes a demo doesn't do a game much justice. A game I was hyped and excited for was Bayonetta and the demo truly sucked on 360 so I decided to pass on it. The game still got great reviews so eventually I went ahead and rented it from gamefly several months later. The rental totally blew me away so I bought the rental.