Broken Chain
If you have a chain breaker push the damaged pin out and re-connect your chain at the next sound link. Shortening the chain might make it difficult to ride in the big ring in and big cog in rear. If you don't have a chain tool, you might have to improvise by using a fist size rock. Yes, it does sound primitive but effective if your ten miles away from anything. The best process for this method would be to place the back side of the loose link onto a similar sized rock then pound the pin in with the rock in your hand, if this works be very gentle riding back to your car.Whenever a chain breaks you should replace your chain before your next ride!

Bent Rim
If the rim is slightly bent it can rub on your brake pads, frame, or chainstays. First try to loosen the brakes or release the straddle cable. If you have a spoke wrench use the brakes as a guide and tighten/loosen the spokes. If your wheel is bent side to side, first you are going to have to release the brake and remove the wheel from the frame. Check for broken spokes and try to remove any if possible to keep them out of the way. You can also twist them around the next good spoke. Try to place your bent wheel against a tree holding the bent sides, then with a few quick jolts try to bend the wheel back to ridable state. This process may have to be repeated a few times depending on the condition of the wheel.

Bent Chainrings
Your crescent wrench out of your tool kit is going to be the best tool for the job in this case. Place the tool over the part of the ring that is bent, making sure it clears the chain rings teeth, keeping them from snapping off. Once you have the wrench in the proper position, push or pull the bent part very gently to try and realign the ring back to its normal position.

If it is unrepairable put the chain in the middle chainring and just use your lower and middle ring until the upper ring can be replaced. Check the bottom bracket before you come to the conclusion that your chainring is bent, because you may have also damaged the bottom brackets spindle. A badly damaged spindle means that you will be wlaking home.

Chain Suck
If you do get chain suck on a ride stop pedalling and get off the bike In most cases you should be able to grab the chain and pull it back the same way it sucked up. You may have to use a little force or roll the bike backwards while pulling the chain.

If it is still stuck you may have to detach the chain from the bike with the chain tool, then re-route the chain back through the drive train. Check for any kinks or twists in the chain before you install it back on your bike. This can cause problems in shifting if not checked before installation.