Some links which invoke things that break too often in embedding apps:

1. A normal link
2. A link with a _blank target window
3. 1st link with a foo target window
4. 2nd link with a foo target window
5. A JS onclick handler (click me)
6. view-source:
7. data:
8. A page of mathml
9. about:
10. about:config (copy and paste into address bar)
11. about:plugins (copy and paste into address bar)
12. javascript: (copy and paste into address bar)
13. A secure website
14. user / pass prompt
15. External content type
16. Activex scripting content