* http://www.jetbrains.com/idea/buy/buy.jsp - Java IDE

* http://free.avg.com/download-avg-anti-virus-free-edition - AVG Antivirus

* https://secure.logmein.com/products/hamachi/licensing.asp - VPN service

Berkeley DB is (sort of) of this variety and so is the Aladdin Ghostscript license. Are there any obviously notable examples out there ?

Does anyone has any experience with this model ? From either side - as a licensor or a licensee.

Thanks

(edit) I though I'd elaborate on this a bit. First of all, the context is a standalone application. Its target audience is not dumb users, but the app is not very specialized either. It is equally useful to both the home users and IT professionals.

Secondly, my take on the above model is this. It is viable because it appeals to the users who are

* capable of paying (from the company budget)

* generally feel obligated to pay (due to internal IT practices)

* and who are easier to part with the money (as it's not their own)

In case of home users neither of these three points holds. The only way to facilitate the payment is to appeal to their conscience (by nagging, by enforcing the restrictions via some sort of DRM mechanism, etc) - very .. err .. uncertain and effort-intensive endeavor compared to focusing on commercial users only.

Also, giving away fully-functional version under some sort of a free license effectively counters the need for hacked "full version" and eliminates the need for the licensing enforcement provisions in the application. Former helps to maintain greater control over the installation base and latter makes for a cleaner and simpler application.