Lots of times, newbie home brewers post messages on internet messageboards asking if there's something wrong with their beer because it has some funny looking foam on it and stuff floating around. Well, that's perfectly normal!
The carboy on the right is in active primary fermentation of an ale, just over 24 hours after pitching. The foam at the top is called "krausen". Fermentation is very active, as can be seen by the "stuff" floating around.
In the left carboy is another beer (a lager fermented with ale yeast) which is pretty much done fermenting.
In the middle is a large mason jar full of sanitizer solution. The tubes going into it are blowoff tubes.
The ultra-high tech soda can mod is to keep the darn blowoff tubes from falling out of the water.