Technics: Simulating slow connections

Many VMware and VirtualPC users are in need of simulating a WAN connection: introducing delay in virtual environments is useful to better test scenarios like Active Directory replication, VPN tunneling and so on.
There are at least three solutions to do that:

1. (only for VMware users) Use virtual serial ports
This isn’t the best method since you cannot choose any delay you want.

2. Buy an expensive solution called Shunra\Cloud
It works on Windows OS and costs about $5,900.

3. Create a new virtual machine for a liveCD OS called m0n0wall
It’s a FreeBSD custom environment created to be a light (only 5mb ISO) and secure solution. It has a traffic shaper feature, ideal to simulate a WAN connection.

4. Download (and eventually buy) a software called MikroTik RouterOS. A free license exists with some limitations.
While m0n0wall can route statically this one can route using RIPv1 and v2, OSPF and BGP.