Brewing - How badly does fermentation smell and what can conceal it?

[paranoid_android]

Not much surprise here if you read the title: does fermenting one's own alcohol smell that bad? If so, what cheap (read: free) measures can be taken to eliminate, dissipate, or otherwise conceal the odor?

My first thought was to use what amounted to a homemade bong, with tubes on both the stem/bowl and mouthpiece. The tube going into the stem would come from the fermenting mash, and the mouthpiece tube could either be vented or perhaps passed through a crude filter of some sort.

If SwiPA did something like that, would there be some sort of liquid he could place into the bong/lock/filter that would help mask the smell?

One more thing to consider: the process will take place in a closet in SwiPA's room. If the smell is only noticeable close to where the fermentation is taking place, please let me know.