is there a clock application,
- that can be placed on your screen like a widget
- staying always on top
- but automatically fades away on mouseover
- enabling you to click through it on items below,
(behaves pretty much like the Ubuntu notifications in that sense).
I am aware, that there are screenlets and gdesklets widget apps, but those are buggy, look outdated, and do not comply with the criteria listed above.
What I have in mind is a clock that is large, (digital), always visible (on top of all other windows), and does not disrupt your work (e.g. you can still click that scroll bar or button if it is just below the clock, since the clock fades away on hovering).
A tool called "OSD-Lyrics" that show lyrics for songs and behaves exactly the way I described above.
So it should be possible (and even easier) to do the same with a clock.