HyperCard http://www.apple.com/hypercard/
The original.

SuperCard http://www.incwell.com/SuperCard/supercard.html

ToolBook http://www.asymetrix.com/products/toolbook.html

MetaCard http://www.metacard.com/

Visual Basic http://msdn.microsoft.com/vbasic/Default.asp

Delphi http://www.borland.com/delphi/

Sash http://sash.alphaworks.ibm.com
This might be a bit of a stretch, but there are some good ideas here.

Squeak http://www.squeak.org
Again, a bit of a stretch, but probably some relevant ideas.

REALbasic http://www.realbasic.com/

Authorware http://www.macromedia.com/software/authorware/

Do Director Shockwave and Flash qualify?

It has been a while since I worked on Unix, so if there are relevant
Unix/Linux products, please reply to this message with your additions.

Note that I have not included products designed for backend web
applications. I'm assuming the focus is on client-side or standalone
applications.

ka