Linux: Where are the Applications? How can I launch my own hacks?

Q: So where are the Applications in Linux?
A: /usr/share/applications/

Create a shortcut to this folder in your file manager, and you've got something like the Mac Applications folder.

/usr/share/applications

Q: That's fine - but how about my own homemade hacks.
A: Yeah, create a hidden folder in your home directory. Add a launcher there.
Q: Launcher?
A: A file with the extension .desktop - like this:

[Desktop Entry]
Name=YourHack
Exec=/pathTo/yourHack
Icon=tux.png
Type=Application
Categories=GTK;GNOME;Utility;

A: Save your hack as, say myHack.desktop. Make the file executable:

# chmod a+x myHack.desktop

A: Now you should be able to see the icon in the folder. The last step is simple - in say Ubuntu just drag the file to the panel. Other windows managers may add the app launcher in other ways.