12.2.9 Projects. Ways to increase the Bill Rate without having a different Rate Schedule

I know one way is create a unique Rate schedule and assign it to a unique task. Other ways to do this?

We want to bill a premium revenue rate for weekend work without creating a unique task. Burden and Labor costs are NOT to be increased. (Salaried workers are not subject to OT rules, but we want to bill the Project a premium for work done after hours).