Omnis Classic Forever young
Omnis 7.3 (or 'cube') was launched 1994 following the infamous Omnis 7.2 ('square') and quickly conquered the Omnis community. Several small service releases followed (1-8) till 1999, but the program widely stands untouched till today. Can you think of any other program originating from 1994 that still works with the current Windows 8 version without major problems?
Omnis 7.3 - now refered as Omnis Classic - is still widely in use. For many developers and users, the upgrade path to Omnis Studio was either too expensive (as you would have to pay a substantial fee for every seat) and/or too time-consuming, as the paradigm shift from 4GL to OOP would have required a complete rewrite of your applications.
Anti-aging Omnis Classic
Omnis 7 was launched at the start of Windows 95. Many GUI concepts like tab-panes or treelists were still to come and not implemented. However, with a little effort you can have those features also in Omnis Classic. Amazingly, you can even implement object oriented approaches with some twists. This page will help you with resources, code samples and - if you want - the magic shell AppliCat, that allowes you to unleash and utilize hidden features of Omnis Classic.