Escaping $ in regular expression

[asterix299]

I'm using preg_match() and I am trying to search a string for a bunch of characters but the $ is giving me a ton of grief...

I have attempted the following forms of escaping it:

'/\$/'

'/\\$/'

//and

'/\\\$/'

//I've also attempted this using double quotes with no luck... 

So how do you escape a $ character within a regex in php?