How do I display changes made by user

[Rick Sample]

I want to be able to display all work done each day by WF developers.
I need to document what I and other have been working daily / weekly.
If nothing exists in SAP admin, I would like to run a report to display
objects changed
by user in a given date range.
 
Nothing fancy. Something simple so I see what I and other have been
working on for a given time period.
Any tips or utilities would be greatly appreciated.
 
I thought I saw an option to for this somewhere but can't remember
where...
 
TIA
 
Rick Sample