Here is a list of supported formatting vB code:

[b][/b] bolds things: b
[i][/i] puts things in italics: i
[u][/u] underlines things: u
[size=num][/size] changes text size to num: size
[color=clr][/color] changes text color to clr: color
[font=fontname][/font] changes the font of text to fontname: Courier
[quote][/quote] indicates quoted text : [quote="name"][/quote] indicates quoted text with the name of the source : [glow=color][/glow] glows things in color:

glow

[alpha=number][/alpha] makes things transparent number is how visible(%) great for smilies:

alpha

[spoiler=clr][/spoiler] makes things readable only by selecting them by making the bg and fg colors both clr:

spoiler

[indent][/indent]adds a left margin to text:

This is indented

[sarcastic][/sarcastic] adds rolling eyes behind text: This is so cool
[edit]nevermind[/edit]Makes it clear that you changed something:

Edit:

nevermind

[fliph][/fliph] flips text horizontally:

flipped

[flipv][/flipv] flips text vertically:

flipped

Put a [color=black][/color] inside [spoiler=clr][/spoiler] to make normal text with a colored bg:

spoiler+color

Other combinations will yield other cool effects.