When you have a list of files (eg, in an FTP view), you can type the filename characters to jump straight to the file. For example, in my case, if you type S-R-M in quick succession, it will jump to the file SRM001. However if I want to jump to file SSM001, and type S-S quickly, it will instead take me to the second S* file. I haven't been able to find any configuration items to change this behaviour.
I have attached a short screencast demonstrating this behaviour.