Snarl works good.
Snarl has 4 options to place notifications:
Top left - it's disturbing me there
Top Right - I used it until today, it's almost perfect but covers minimize and close buttons of fullscreen windows.
Bottom Left - I use it now, need to get used to it, but it's ok
Bottom Right - My first try but firewall and other things show something there so it would be hidden.
This was just to show why I request this.
- Right side at the top, but lower (maybe user defined space from top)
- Right side middle of screen.
- where ever you can imagine to show them ;) (maybe a totally user defined place XxY)
I hope this is your taste.
(R2.1 Beta 1 (V39.6))