Javascript to open a folder on local computer

I currently use formula-text buttons with Javascript to open remote URLs. This works great. But I also want to use the same technique to open a folder my local Mac (so I can save files).  In Mac, you can use a link from the finder (file:///Users/drivename/folder/folder...) format to get to files NP. But unfortunately dropping this link into the formula text field or a URL doesn't work I'd think some javascript might be needed to advance this functionality?  
If the link above is listed and you right-click on it then choose "services" and the choose "Open URL" it does work..but that's too many keystrokes...can anybody help?