What are some simple muscle gain/fat loss exercises with no gear?

What are some simple forms of excersize you can do with nothing but 8 lb. weights and no bench? I am looking for something more creative than sit up or push ups but I do those too.

You can try different variations, also there is chin-ups and pull ups... Hmmm... when I first started working out a grabbed a bunch of 2L bottles and filled them with water, I then put the bottles in a gym bag and did raises over the back of my head . (position yourself on your knees and pull from the front, then over your head behind your back) just keep doing that over and over, it will build some muscle and burn calories.

...body walks (a variation of squat-thrusts).