"Sneaky" training

Even if you're really busy or not training on a certain day, there are still some ways to strengthen your muscles and keep healthy (some of them also give you a little boost). Here are some things that I do (whenever I remember them! XD) some of them are from other sources and some I discovered myself:

• When walking (or running) up a flight of stairs there are two ways people usually place their feet: One is like a Barbie foot, using only the ball of the foot to land on the step - this would work the thigh muscles. The other is flat with the arch of the foot also landing on the step - this way would strengthen the calf muscles more than anything else. (I haven't done any research on this, it's just my finding. Maybe it's different with different people.)
• Whenever you take milk out of the fridge (especially if it's a full jug), raise and lower it - only moving your forearm - 5 - 15 time then repeat with the other arm.  Just don't drop it! 
• When sitting somewhere for a long time (at a play, sports game or what have you) make sure to sit properly (feet flat on the floor, back straight, chin level) and then contract your ab muscles tight, count to five and relax. Do this no more than 5 times, waiting a minute or two between each time. 

So far that's all I can remember, but here is a good list of more ways to sneak training into your daily routine.  (Some of them are for people who go to school, but still.)