As we go through our days, we are constantly on the look out for those items for household living that are just indispensable and make us happy whenever we use them.
The most recent one we noticed in our own home was the Vacu Vin Wine Saver...
We drink a great deal of wine, but we don't always finish the bottle. When you simply put the cork back in, it never tastes the same a day later, never mind a few days after that. However, when you put one of these stoppers in and suck out all the air oxidation nearly halts and you can preserve wine's best taste for a really long time (a week is no problem). The Vacu Vin Wine Saver is available in lots of places for $12.99.
While we thought it was a bit of a gimmick at first, we now use this thing on every bottle and end up with little grey stoppers all over our house. (Re-edited from 2005-10-21 original post, Maxwell)