Hello, beatiful world!

I am exploring Shell extension (and COM Object, in gereral) on Windows XP. And I've seen, that some applications, like Dropbox, are somehow "activates" shell extensions after application's launch. I was wondering how it may be done.

Here is some advanced information I've been able to get regarding Dropbox:
There are two interfaces (IContextMenu and IShellIconOverlayIdentifier) that, according to registry (and tool ShellExView), are implemented by in-process server DropboxExt.14.dll. Howerer, Dropbox's overlay icons and context menu items appears only if application itself (Dropbox.exe) is running. May be there is a way to somehow "bridge" implementation from *.dll to *.exe when the latter is running?