I just spent 2 hours in HTML/CSS/Browser-Compatility-Layouting-Hell again. Worked on a small new website which needed to work on Opera, various versions of FireFox, Safari, InternetExplorer and - although it is nearly dead - IE6 as well. Basically this is quite easy to achieve if you just take a fixed layout and a few images, but doing this with a variable sized layout and multiple files of complicated CSS ensures a lot of fun.
And doing this without special browser version checking really IS hell. Especially if you really need IE6 compatibility, there are
some countries which heavily rely on this browser.
Just thought of never doing web development work again... On the other hand, I promised myself this several times before already. :)
It's the only area of the computing world that requires you to keep compatability so far back, most hardware vendors don't even support drivers in past operating systems and since when can you run DirectX 10 on Windows 3.1 the rest of the world moves on but the web keeps on chugging on IE6! - Get over it and upgrade! Although I did read somewhere that the WGA program stopped most folk upgrading to IE7 which explains a lot.