While watching the Deep Dive on Designing a BranchCache Infrastructure presentation I noticed the Network Emulator for Windows Toolkit (NEWT) that Tyler Barton was using to simulate a slow network link during his BranchCache demo. 
After a quick search I’ve found a compiled version for 32 and 64 bit here provided by Marco Pol. NEWT is a Very useful easy to use tool if you want to simulate a slow network connection for testing BranchCache, Group Policies, Software Distribution or just for demonstration purposes.