usage:
	sdesk [-i file(s)] [-b image] [-t image tooltip left-action right-action]
		-i             full path to file(s) with shell functions to include
		               by default it looks in /usr/share/sdesk/func*
		-b <file>      file to set desktop background image
		-t             tray icon must have the following parameters:
		  image        full path to image file
		  tooltip      full path to tooltip file or a "quoted tooltip"
		  left-action  action to run when left mouse button is clicked
		  right-action action to run when right mouse button is clicked
	The -t option may be repeated as necessary for multiple tray icons.
	The -b option is subject to change as it is currently hard coded to output
		the button/key presses to stdout for a user program to handle instead
		of handling it internally

besides being able to create tray applets using -t, it is possible to create
desktop widgets by using an svg image and including embedded images, text,
graphs, etc... such as:
webcam viewer - use ffmpeg to output to an image and embed it in the bg svg
channel preview - you can use ffmpeg and a tv tuner to get snapshot previews
partition usage - use rectangles and text on the bg svg
desktop icons - more difficult but you can track position of them and run an app
graph anything - signal strength, web site status,... anything
show notifications - use text boxes to display text (or even files via tail)
see pwidgets, gkrellm, and other for some ideas