How to access files on PC (from a PC on a different network)

Good day. I have a PC running Windows 7 Home Premium at my shop. I want to be able to access the files and folders on my shop PC from my home PC (which is obviously on a different network). Any suggestions on how I could do that would be appreciated.

Thanks.

You may want to have a look at this.
https://secure.logmein.com/welcome/...57021&ef_id=zTVOjh-C3lAAAEqU:20111107165753:s

Thanks for the reply. As far as I know, logmein allows you to log into the computer, but it takes over the screen, so if someone else at my shop is working on the computer, that would interrupt them. I want to be able to access the files without affecting someone at my shop that is using the PC. Maybe I am missing something about logmein?

ah perhaps you want a ftp then?
FileZilla - The free FTP solution