Apparently this prints out 99 bottles of beer on the wall. I'm not joking when I tell you that this is a dear language. This is just crazy.
Code:
##########################
### 99 Bottles of Beer ###
### coded in Brainfuck ###
### with explanations ###
##########################
#
# This Bottles of Beer program
# was written by Andrew Paczkowski
# Coder Alias: thepacz
# three_halves_plus_one@yahoo.com
#####
> blank the zeroth cell
+++++++>++++++++++[<+++++>-] 57 in the first cell
+++++++>++++++++++[<+++++>-] 57 in second cell
++++++++++ 10 in third cell
>++++++++++ 10 in fourth cell
##########################################
### create ASCII chars in higher cells ###
##########################################
>>++++++++[<++++>-] " "
>++++++++++++++[<+++++++>-] b
+>+++++++++++[<++++++++++>-] o
++>+++++++++++++++++++[<++++++>-] t
++>+++++++++++++++++++[<++++++>-] t
>++++++++++++[<+++++++++>-] l
+>++++++++++[<++++++++++>-] e
+>+++++++++++++++++++[<++++++>-] s
>++++++++[<++++>-] " "
+>+++++++++++[<++++++++++>-] o
++>++++++++++[<++++++++++>-] f
>++++++++[<++++>-] " "
>++++++++++++++[<+++++++>-] b
+>++++++++++[<++++++++++>-] e
+>++++++++++[<++++++++++>-] e
>+++++++++++++++++++[<++++++>-] r
>++++++++[<++++>-] " "
+>+++++++++++[<++++++++++>-] o
>+++++++++++[<++++++++++>-] n
>++++++++[<++++>-] " "
++>+++++++++++++++++++[<++++++>-] t
++++>++++++++++[<++++++++++>-] h
+>++++++++++[<++++++++++>-] e
>++++++++[<++++>-] " "
++>+++++++++++++[<+++++++++>-] w
+>++++++++++++[<++++++++>-] a
>++++++++++++[<+++++++++>-] l
>++++++++++++[<+++++++++>-] l
>+++++[<++>-] LF
++>+++++++++++++++++++[<++++++>-] t
+>++++++++++++[<++++++++>-] a
+++>+++++++++++++[<++++++++>-] k
+>++++++++++[<++++++++++>-] e
>++++++++[<++++>-] " "
+>+++++++++++[<++++++++++>-] o
>+++++++++++[<++++++++++>-] n
+>++++++++++[<++++++++++>-] e
>++++++++[<++++>-] " "
>++++++++++[<++++++++++>-] d
+>+++++++++++[<++++++++++>-] o
++>+++++++++++++[<+++++++++>-] w
>+++++++++++[<++++++++++>-] n
>++++++++[<++++>-] " "
+>++++++++++++[<++++++++>-] a
>+++++++++++[<++++++++++>-] n
>++++++++++[<++++++++++>-] d
>++++++++[<++++>-] " "
++>+++++++++++[<++++++++++>-] p
+>++++++++++++[<++++++++>-] a
+>+++++++++++++++++++[<++++++>-] s
+>+++++++++++++++++++[<++++++>-] s
>++++++++[<++++>-] " "
+>+++++++++++++[<++++++++>-] i
++>+++++++++++++++++++[<++++++>-] t
>++++++++[<++++>-] " "
+>++++++++++++[<++++++++>-] a
>+++++++++++++++++++[<++++++>-] r
+>+++++++++++[<++++++++++>-] o
>+++++++++++++[<+++++++++>-] u
>+++++++++++[<++++++++++>-] n
>++++++++++[<++++++++++>-] d
>+++++[<++>-] LF
+++++++++++++ CR
<[<]>>>> go back to fourth cell
#################################
### initiate the display loop ###
#################################
[ loop
< back to cell 3
[ loop
[>]<< go to last cell and back to LF
.. output 2 newlines
<[<]> go to first cell
###################################
#### begin display of characters###
###################################
#
#.>.>>>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>
#X X b o t t l e s o f b e e r
#.>.>.>.>.>.>.>.>.>.>.>.
#o n t h e w a l l N
#<[<]> go to first cell
#.>.>>>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>>>>>>>>>>>>>.>
#X X b o t t l e s o f b e e r N
#.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>
#t a k e o n e d o w n a n d p a s s
#.>.>.>.>.>.>.>.>.>.
#i t a r o u n d N
#####
<[<]>> go to cell 2
- decrement cell 2
< go to cell 1
########################
### display last line ##
########################
#
#.>.>>>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>
#X X b o t t l e s o f b e e r
#.>.>.>.>.>.>.>.>.>.>.
#o n t h e w a l l
#####
<[<]>>>- go to cell 3/decrement
] end loop when cell 3 is 0
++++++++++ add 10 to cell 3
<++++++++++ back to cell 2/add 10
<- back to cell 1/decrement
[>]<. go to last line/carriage return
<[<]> go to first line
########################
### correct last line ##
########################
#
#.>.>>>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>
#X X b o t t l e s o f b e e r
#.>.>.>.>.>.>.>.>.>.>.
#o n t h e w a l l
#####
<[<]>>>>- go to cell 4/ decrement
] end loop when cell 4 is 0
>[>]<. go to last line/carriage return
<<<.<<.<<<.
n o
<[<]> go to first zero line
>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>.>
b o t t l e s o f b e e r
.>.>.>.>.>.>.>.>.>.>.
o n t h e w a l l
But yeah, Brainfuck is a bit of a.. brain fuck, when it comes down to it. It's really interesting, but I have no idea why people would actually use it over "higher" languages.. other than for the challenge, I guess. It's doesn't seem really worth it to me, but I guess a lot of people have fun with it..