Synchronize with WordPress/BuddyPress accounts

I'm not sure if it's possible, but would be a great idea!

Create a way of letting people synchronize WordPress/Buddypress user accounts with OpenCart so for people like myself, whos running a wordpress website, and wants a webstore but linked outside of the site using OpenCart, people can use one single login/pw.

I have been hunting for a solution for this for nearly 2 weeks, I have googled every way I can think to ask the question and all I keep finding is others asking for the same thing and never an answer. Surely someone can do this. I really wish I could but I am just not that clever. Please Please all you clever coders can someone make an extension for this.
Alice.