Developing content for the web is frustratingly limited. That's no secret. What are the top must fundamental missing features that should long ago have been fully and completely solved? Here's my quick hit list:

#1. Fonts. Any font should be able to be easily referenced on a web page universally. I know you can embed fonts for some browsers but there are no good ways to really embed a custom font that everyone will see. As a result, we spend all day looking at boring (though readable) fonts. Now, I know some of you will react by saying "Thank FSM! I don't want to squint through someone's idea of a cute handwriting font to read their page." I say, let the market decide. If you make an ugly page, people won't go there. Enough said.

#2. Curved Lines. I don't really care if this is a full blown vector art implementation like SVG (see: Wikipedia for browser support of SVG) but for fsck sake at least some native curved border corners would go a long freaking way.

#3. Columnar Flow. I should be able to have text flow in a two or three column mode, such that when it reaches the bottom of the space the overflow starts at the top of the next column. As wide screens become more and more popular, we either end up reading sentences that span 12-14 inches of screen real-estate (which isn't comfortable) or dividing all our pages into less natural formats just to get the effect of columns.

#4. Calendar Cookies, Contact Cookies, Etc. The idea is that there should be a standard way for a web page you're viewing to offer you a calendar entry such that your browser would know to launch out to your calendaring program for the interaction necessary (like availability checking, or adding the entry as an event mark, or whatever). The same hold true for contacts.

#5. Telephony. A 'click to call' standard would go a long way.

What else? What design functionality is just broken?