It's well-documented that it's easy to whiz around a webpage thanks to the flicks and gestures Safari on the iPhone supports, but anything that cuts down on clicking and dragging is a Good Thing to my mind and so here's a handy surfing tip.  If you're reading a page that lacks a "return to top" link at the bottom then just tap the top status bar (where network, signal strength and time are displayed) and it'll automatically shoot to the top of the page.

This works well with other iPhone navigation tips, such as tapping the screen mid-scroll to stop it dead rather than let it come to a natural halt.  Also, should you be viewing a webpage with a frame that on a desktop browser would have a scrollbar of its own (but which Safari on the iPhone doesn't display) you can scroll that frame individually by tapping and holding in it with one finger and then scrolling with another.

What shortcuts and navigation aids do you use most often?  Let us know in the comments.