Caro-Kann 3...c5

I think it's called the Arkell/Khenkin Variation and has been used by GMs in Wch matches (Tal - Botvinnik, 1961?) so it's definitely playable at the club levels.  Black uses it to sidestep existing theory/preparation by White. There's already been a heated debate on this in these forums.

http://www.chess.com/forum/view/chess-openings/caro-cann-advance-variation-with-3c5

I have played 3...c5 a few times, but it may be too risky.  Here is a game I won with it., but poor play on my opponent's part.

Thanks guys. I'm glad that there are GMs who play this because I like the way it looks for Black (probably because I also like the QG). Anyway I played a game against the computer on here.

Quite right.  If Black plays ...e6 without developing the Bc8 outside the pawn chain, the game is more like a French Advance set-up at the cost of a tempo.  Nonetheless it does get played surprisingly often, although the stats aren't very good.

4 ...Nc6 is more principled and better, IMO.

3 ...c5 is certainly playable.  Personally, I much prefer 3 ...Bf5 and see no reason to change.  There is more to learn, obviously, but it's worth it to me.  I like Black's game.

From someone who's playing the opening for one of the first times, the move ...e6 feels more comfortable to me. It avoids Bb5 and having to play ...Bf5 which is a move delaying the recapture of one of White's pawns. In the game I played above, the light squared bishop was very passive for the entire game and I can see why 4...Nc6 might be better.

Ajedrecito has me convinced (by the lines he provided) that 3...Bf5 is better (for me). After 4...Nc6 5 Bb5 I don't like the way Black's position looks and 4...e6 leaves a weakness.

Here are the lines that ajedrecito mentioned:

Those are the 3 ...Bf5 main lines - I play them myself as my first-line defense v 4 Nf3 and 4 Nc3.

I should mention that in answer to dxc5 the only move for Black is ... - e6. Other are too risky.

I do very well in the Bf5 advanced variation, don't see the need to change from that at my current 1800-1999 uscf level (it's the Panov that frustrates me ). Maybe surprising your opponent in the opening is a concern at expert/master level, but until then I would focus on outplaying your opponent in the middle game. After exchanging on d4, try abusing the open c file with your rooks and queen. It can be effective.

I could not disagree more.  In fact, if Black intends to answer 4 dxc5 with 4 ...e6, I think he will be better off avoiding 3 ...c5.

I agree with Fezzik also, and have found I have better results when I am willing to sacrifice a pawn in the C-K than when I tried to passively hold the fort.