The post Write Stylesheets Simultaneously has a great tip for easing the initial development of a new site. Instead of manually reloading your browser each time you want to view your changes to your markup or CSS, throw a simple meta refresh into the HEAD so the page will reload automatically every N seconds. A second tip is provided a bit farther down the page – so check it out.
CSS
Clearing floats without structural markup in IE7
Nifty Corners Cube
Nifty Corners Cube is an image-free way of building rounded corners!
Unitless line-heights
Eric Meyer sheds some light on the interesting application of line-height within the cascade, specifically he recommends implementing Unitless line-heights (‘1’ instead of ‘1em’ or ‘100%’ for example) in order to avoid the wrong values flowing down the cascade to descendant elements. I highly recommend you check it out should you be a Web dev type of person.
Toggle (show/hide) elements in a Definition List
Vertical-Align Misuse
Nick Gagne has posted a great explanation of the vertical-align
property which is a must read for every front-end Web developer. The examples wrap it up beautifully. Good stuff!