To name off specific apps is being a short-sighted fool. The best idea, as Wayne has done, is name off needs rather than tools. You never know where the next Quicken or Lotus 123 will appear.
So how about we keep this focused on needs.
What I need is:
1) A fully object-oriented desktop experience
2) Integrated networking stack
3) Integrated preferences system
4) Web browser that can fully support XHTML 1.1
5) XML support is a must
6) IPC system
7) fully documented

Games, need original game ideas. Don't need the next Quake3 here, but need originality. Sometimes the best games can come from the most unexpected areas.