If you have a few tomatoes that are half ripe in the garden, pick them and let them ripen slowly on the window sill. This keeps them from ripening too fast on the vine.
To keep your tomatoes fresher longer when in the fridge, store them with the stems down!
If you have lots of tomatoes but don't have the time to make sauce, here is a great tip: just wash off the tomatoes, put them on a baking sheet. Freeze the tomatoes over night and them pop them in a sealed baggy. When you are ready to use them, thawing the skins will peel right off and you can slice them up for great additions for your home cooked meals without the fuss!