Ever been to a situation where the opponent wins your queen straight off the bat? Most people would resign right? Would you?
Funnily enough, in blitz and bullet, chess is run by psychological emotions more than calculations. After your opponent wins large amounts of material, he is expecting you to resign. If you play on, his playing stength will decline by 300-600 points. The more annoyed and frustrated your opponent is feeling, the better.
I've been situations like these and my advice is to never give up until you are checkmated. Your opponent often start to play horribly after they win material for a number of different psychological reasons. If you stay cool headed, you actually have very good chances even after losing the queen!
Of course, one should not simply hope for a miracle. There are actually special ways to play when being down large amounts of material to increase your opponent's annoyance and therefore the probablilty of blundering. I'm gonna try to cover most of the strategies that I use.
1. Don't get flustered. Stay focused and concentrate on finding all the tactical resources you can
2. Play trolling moves. Attack anything (especially the queen) as many times as you can so that he can't do anything constructive
3. Alternate your pace. Play really slow on one move and really fast on another. This throws your opponent off, kind of putting him on a seesaw in which he is over relaxed at one moment and extremally paranoid in the other
4. Play really weird moves. This forces the opponent to think thereby increasing his chances of blundering or getting timed out
5. Have a general plan of how you are going to troll the opponent. One large plan is a bad stragegy given the large material deficit. Have a number of very small plans available to set the pieces temporily to give a direct threat. Then, after he deals with the threat, switch gears and set up another threat. The goal is to troll him/her so much that they start giving you back increasing amounts of material thereby increasing your chances
5. Avoid trading. Even for winning a few pawns, it is not what you should do. This is what the opponent wants! Don't trade anything!
6. Constantly look for activity. Never get passive. You want the game to be open even at the cost of a few paawns.
7. Be patient and your opponent will begin to make increasingly large blunders.
Of course, against a strong minded opponent, you will still lose. However, you may be surprised at the number of games you actually win even against equal or stronger players. Psychology plays a very large role in blitz and bullet chess. I recently played an online game where I actually beat a player down a queen. The player was actually higher rated than me by about 40 rating points.
Here it is:
Ahhh, I love psychology.