Speed Changer
Allows to adjust the speed of the game.
The main difference from Smart Speed is that you can set the speed lower than the default.
To disable slowdown, use No Forced Slowdown mod.
Incompatibilities
Most likely not compatible with mods of similar functionality.
FAQ
Q: Is this mod save game compatible?
A: Yes, you can add it whenever you like.
Used source code from Smart Speed
Thanks to Sarg Bjornson