And, of course, oil lamps ...
These beautiful jars can also be used to make candles and I have seen them sold at various places such as flea markets, festivals, and candle shoppes. Here is a handy little link on how to make your own candles out of Mason jars: http://www.wikihow.com/Make-Mason-Jar-Candles.
Historically speaking, the Mason jar has been around since 1858 and was originally invented by a tinsmith from Philadelphia, PA named John Landis Mason. They are also known as Ball jars after the Ball Corporation who sold them mainly as fruit canning jars and glass canning in general.
They now come in many colorful assortments, including pastel, and remain a very popular collector's item which can be bought and sold at most antique stores and auctions as well ~ including e-Bay.