I was playing around with a workflow where needed to have different functions depending what day of week it was. So I manage to find some old code there actual worked.
I compiled the WFA and registered it into CRM and the magic happend I was feeding it with the run date of the workflow, and then it return the name of day
If you need more info on how I did this let me know and I will help you.
Please place a comment if you want me to publish an article regarding this, then I will spend the time on it