A good post on Top 50 Linux Alternatives to Microsoft Applications:
http://jjmacey.net/blog/?p=179

Another good site I have found is OS Salt (Open Source Alternative):
http://www.osalt.com/

Feel free to use them to find alternatives, as the titles might suggest.

Cheers,

Craig H. / "xq"

P.S. - Do you have any applications you suggest that are not on the list?