Shareware - how to encourage purchase?

[Clearcode]

If you want to provide a try-before-buy piece of software but still encourage the user to actually buy the software, what is the best way to go about this?

[Manish Malik]

Limited Functionality Version.

Having a different version altogether (no...don't use the full version with a couple of "if"s for limiting) prevents wide availability of cracks for your shareware. (It however, means, now your full version must be available for non-payers to get away with it).

[dlorde]

I favour a full-spec release with random nag screens (on random actions/commands) that start at the free-trial expiry time and get more time consuming every time an action/command is used.

Of course, it's easier to describe than to implement ;-)