CSS3 and WebKit make using a custom cursor extremely easy, but just because you can doesn't mean that you should. There are many uses of these in the wild including this forum. I personally believe that it is fine when you are developing a dark theme for your site. What do you web designers think of using these?
My oppinion, ever since html1 times.. do not f**n mess with my cursor! There is no valid reason why the cursor must be altered ... it changes relative to the context anyway.
I would be looking for ways to block that "feature" as soon as the browsers start to fuck with it
Not a web designer, but have come across many sites with custom scrollbars. Depends in the direction you go. Slightly smaller and coloured to blend in with the page style work really well like on here. But you can easily match them too closely and lose track of them, the blend in or are too small to see easily.
Custom cursors in general have no need to exist most of the time and thankfully most websites stay away from them.
Web designer here. General rule of thumb it's a bad idea to change browser/system controls that the user is used to purely for aesthetics. Keep the cursor to the generic stuff, save when you're changing it to indicate how the item being hovered over can be used-- ie: text uses a text cursor, links and buttons use a hand, etc. Anything else is not worth it.
absolutely do not touch users cursor.
Max you should do is cursor: pointer on clickable things, text on inputs or disabled on disabled buttons. But no custom fancy '00 style pink unicorn cursors, or i will find you and take your computer away from you! :D
Custom scrollbal should be option only if you have lets say 100% height fixed sidebar, that has more content inside than it can fit on screen and default browser scrollbar would look really ugly. But do not touch scrollbars unless its really necessary