A really trivial nitpick about the clickable discussion titles in this forum
When you are looking at a list of discussions in this forum, you can click on a title to read the discussion. When you mouse over the title to click it, it changes colour to blue.
However, the HTML element which contains the :hover attribute for changing the colour of the title text is not the same as the anchor that contains the text, and is larger than it on the screen. So it is possible to place your mouse in a position which turns the title blue, but cannot click on the title.
The issue is that (in common with almost all hyperlinks on the worldwide web) the changing title colour is a really big clue that you have moused over a clickable link, so it's an instinctive reaction to click as soon as it changes colour. But if you clicked the outer container without clicking on the hyperlink itself, the click won't work, and you spend the next 5-10 seconds waiting for nothing to happen. It interrupts the flow.
So, this is a really minor point, but I can't see any valid reason why there should be an element that changes colour on mouse hover but which isn't clickable.