I wanted to thank you for this fantastic site. For me it is the best site for softimage and any other dcc. I hope it will stay long with us. For me Softimage is still the best tool, simply because it is so thoroughly well designed.
SOFTIMAGE 4EVER !!!! 
Okay, here is another nice plugin which adds some smart enhancements for modeling workflow.
What does it do?
This plugin, called SmartKeys, makes it possible to use for example the key UP and key DOWN on your keyboard for changing some of the important parameters of an operator at the top of the modeling construction history.
At this time you can do the following adjustments:
-Increase/Decrease U Subdivision of primitives
-In Subdivide Edges (evenly) adjust Subdivisions parameter
-In Split Edges adjust the Ratio Edge parameter
-In Extrude Along Normal adjust Length parameter
-In Inset Polygons adjust the Inset Amount parameter
-In Bevel Components adjust the Distance parameter
I assure you it is really handy to change these parameters in a fast way with your keyboard. Remark: It works only on the top modeling operator but in a context sensitive way.
How to install?
Install the xsiaddon file SmartKeys.xsiaddon with File -> Add-On -> Install...
When the addon is installed you can assign some keys to the commands. Go to File -> Keyboard Mapping... In the group Custom Script Commands there are two new commands: SmartKeyUp and SmartKeyDown. Assign the keys you like, for example the UP and DOWN keys respectively.
Here are some examples, I hope the gifs work:
See Attachment for plugin files (thanks for advice!)
I think I will extend this plugin further with some additional functionalities, but it will take some time. Hope you like it!
