I use dropzone quite  a bit daily...
Zip and Email: I have to email people work quite often and this helps when attaching files
Install Application: I tend to find new apps quite a often so this helps when installing them smile
FTP: I have a folder set up so when I want to share a video, files, zip etc so really handy to be able to just drag it over to get a link
Remove App: This opens App Delete with the application, for when I no-longer want to use something
Print: Printing all my work...
Bit.ly: Don't really use that much... But seem to have kept it in my dropzone grid
Screen Shots: I use tiny grab but when I also want to keep an image (even though its online) I just drag it over to that file.
Flickr: Don't use this that much either but its good the the times that I do.
Share Text: Sharing text
Rucksack: After I have finished a project I can zip it up quickly and then normally  move it somewhere I keep finished things.