SlackBuildsOrg/system/xosd

XOSD displays text on your screen; sounds simple, right? The difference is 
that it is unmanaged and shaped, so it appears transparent.  This gives the 
effect of an On Screen Display, like your TV/VCR etc.  The package also 
includes an xmms plugin, which automatically displays various interesting 
things as they change (song name, volume etc...)

gdk-pixbuf is an optional dependency, but don't bother - it causes the
build to fail.