In Australia we have different pay rates for for example:
The base hourly award rate e.g. normal pay for weekdays
Saturday hourly rates = 150% of base hourly
Sunday hourly rates = 200% of base hourly
Public Holiday hourly rates = 250% of base hourly
25% casual loading e.g. Casual employees get 25% more pay as opposed to part time and full time employees (who instead get personal and annual leave).

It would be great if you could create pay rate rules that allow you to apply different pay rates to different days.