A few days ago I posted various defenses to a big one (and two) club opening, but I saved my favorite for today: Suction.
Suction (aka Cyclone) is a little complicated, but a lot of fun. Basically, in Suction, you're showing either a one-suiter or a two-suiter, all in one bid. The bid of a suit shows either the next suit up or the other two (never the suit you've bid). For example:
2D = Hearts or Spades + Clubs
3H = Spades or Clubs + Diamonds
1S = Clubs or Diamonds + Hearts
So all one-suiters can be shown in Suction by bidding the suit below the real suit. Touching two-suiters are shown by bidding two suits below the lower of the two. That only leaves non-touching two-suiters: clubs - hearts and diamonds - spades. With these two combinations you bid some number of notrump.
Over all of these bids, responder makes a "pass or correct" bid, usually as high as he can preempt safely. So let's say you have
QTxxx x Jxxx Txx
Your LHO opens 1C (strong, artificial, and forcing). Partner jumps to 3C, showing either long diamonds or both majors. Since he could've just bid 2C showing the same suit combinations, he must have lots of distribution. So what's your bid?
I bid 4S! We either have an eleven-card diamond fit (if partner has diamonds only, he should have 7 since he forced to 3D) or a ten-plus-card spade fit (partner should be at least 5-5 if he has both majors).
Remember: You can't bid your own suit here. You're responding to your partner's suit (or suits). If there's a big misfit, get out as low as possible!
Some enterprising souls play Psycho-Suction. This throws lots of confusion into the auction for both the big club side and the defensive side. Psycho-Suction is just Suction, but one step lower -- so if you have a one-suiter, you're bidding that suit. This has the advantage that responder, hoping partner actually has the suit he bid this time, can pass the Suction bid, but that's not much of an advantage when overcaller actually has the next two suits! Psycho-Suction should only be played by those with a lot of practice with Pass or Correct bids and a good sense for when and how to get out of trouble.
The king of confusion is Inverted Psycho-Suction. With IPS a bid shows either that suit and the next suit up or the one above that! So, over a big 1C, 2D shows either both red suits or spades. To play Inverted Psycho-Suction, the two criteria above are still in place, but you also need both partners to have a very good sense of humor!