expanding select options on open

expanding select options on open

I've seen this before but I can't find it.  It's either javascript or jQuery that expands the options of a select box when it opens.  It's used when the select is in an area that doesn't afford a lot of space.  Before it's opened it's a fixed width.  On open the options expand out to full size.  The select doesn't expand in it's space, the options appear below it much like a drop down list menu on this page:


Is there such a thing or am I SOL?