If you are considering a wine cellar, a wine cabinet, or even a small wine credenza, wine preservation is important to you. You have a wine collection that you'd like to maintain, and if possible, improve the value of. Wine is one of the few commodities that can both improve with age, and to which the wrong conditions can render valueless.

WineKeeper will preserve between 4 and 12 bottles of wine with nitrogen gas to prevent harmful oxidation.
Light, temperature, and humidity are the three factors that have the most direct effect on wine preservation. Light can interact with the wine's phenolic compounds to create unpleasant characteristics. Temperature problems can cause unwanted chemical reactions to take place that can make the wine taste worse or even spoil it. And humidity is required to keep corked wines from drying out.
Because the light, temperature, and humidity are drastically changed when a bottle is opened, uncorked wine doesn't keep for very long. Fortunately, there are systems like the Wine Keeper available that offer the drinker the flexibility to serve a glass or two and preserve the rest for another night. This kind of wine preservation is achieved with nitrogen, allowing restaurants and those at home to keep their wine fresh for multiple nights.
Another option for wine preservation is a wine preserver, with uses argon gas to keep wine out of contact with the air and protect it from being oxidized. Argon gas has been judged more effective than nitrogen by many professionals at displacing the air from the top of an opened wine bottle. Some wine preservers fit an individual bottle, and so can be stored easily in the fridge.
Wine preservation is a process that can continue even after the bottle is opened. If done right, your wine will remain perfectly preserved to the very last glass.