I dont think you can do that in Imageshack, since its for pictures only, but thats exactly what you can do in dropbox, when you put your files to that "public" folder in either the internet storage space or if you hav synced your computer, to your computers "my dropbox" folders "public" folder.
If you sync with your computer folder, then you just go to that folder of yours and rightclick on that file and choose from rightmousebutton menu that appears "dropbox/copy public link" and paste that in your forum message, and its downloadable to anyone, example my last months speedcoder entry:http://dl.dropbox.com/u/3375468/Wanderi ... be-win.exe
i dont know how to get those links if you dont sync your computer with your dropbox webfilespace, but basically you can figure out the links yourself if names are short.
ie, if i upload a file name: myfile.exe, link to it would be:http://dl.dropbox.com/u/3375468/myfile.exe
so point is, every files public link constis this beginning of:http://dl.dropbox.com/u/
then comes your user ID, which in my case is:
then comes the name of the file, in this case:
but if name is longer, then to my understandning it will add something like it added on that example link of mine: %20
So even if you dont sync your computer folder with dropbox webspace of yours, as long as you use short file names, its not hard to figure out what that public link for them is and you can post them here.