Yes, CopyMinder makes software rental easy.

You can use the 'expiry date' and/or 'maxdays' fields to specify how long your code should work for.  You can also specify a warning period that notifies the user when the next renewal is about to become due.

By linking CopyMinder with an on-line payment system such as PayPal, you can fully automate the process.

An alternative to monthly rental is to charge users according to how much use they make of your software.  The 'execution count' facility in CopyMinder makes this easy.  Again, by linking it to an on-line payment system, the whole process can be automated.