Here’s a collection of articles on avoiding truncated borders and content when using negative margins in IE6 and IE7:

The Definitive Guide to using Negative Margins
The Positive Side of Negative Margins
Border Chaos
Solution for Negative Margins and Indentation
Clipping of Negative Margined Blocks in a hasLayout Container
Negative Margin hasLayout Bug

Here’s a few articles on improving the performance of dynamic property behavior scripts in IE6 and IE7:

One-time Execution of IE CSS expressions
One-Time Expressions Demo
The Internet Explorer Progress Bar continues to Increase when an attached Behavior is Dynamically Inserted in a Page
Script Error when you send Web Page by E-Mail
MSN Messenger Activities with Simulated Asynchronous Webservice Calls
CSS Behaviors Reference
About Dynamic Properties

Here’s a few articles on variable issues with the iframe tag in IE6:

IE overflow-y iframe Bug
When dynamically generating iframes in IE6 and SSL, their location must be preloaded
AJAX IE iframe Bug
Select Free iframe Modals
iframe shim for Java Applets
iframe shim for Flash Objects
iframe shim for Google Streetview

Here’s a few demos to show how CSS shrink wraps block elements to fit content in different browsers:

Shrink to Fit Boxes
Incorrect Shrink-wrapping in the Presence of hasLayout children
Adjacent shrink-to-fit boxes in IE7
Shrink-wrap and Center

Here’s a collection of browser specific configuration tips for customizing your cross-browser development environment:

Chromium
Chromium Nightly
Chrome User Guide
Chrome About Pages
Chromium Installation DLL
Chrome User Experience
Chromium FAQ
ClickToFlash Chromium Plugin Manager
Undocumented Chrome Execution Switches
Chrome Plugins
AdSweep
Chromium User Data Dictionary
Chromium User Scripts
Chrome Support
Chrome Hacks

Webkit
How to Grab and Thumbnail Websites using KHTML
Working with Webkit Nightly Releases

Opera
Opera Web Developer Toolbar
Cookie Revealer
Google Search Cookie Cleaner

Firefox
Cached URLs
Disabling Plugins in Firefox
Firefox Chrome URLs
Beef up the Find command in Firefox
How to ungrab Firefox hotkeys from Flash players
How to Disable the PDF Browser Plugin for Firefox
Issues related to Plugins
Firefox 2 and 3 side-by-side
Opening a New Instance of your Mozilla application with another profile
Mozilla Preferences Directory
Mozilla Preferences Glossary
Mozilla About:config Entries Matrix

Internet Explorer
Fixing Reliability Issues in IE8
More IE8 Extensibility Improvements
Play with IE8
Session Cookies, SessionStorage, and IE8
Personalize IE8 through Services
IE8 Features Developer Guide
Who Needs IE8 Accelerators

Here’s a series of articles on using MHTML and server-side scripting to create cross-browser Base64 encoded image data:

Use MHTML:URIs when you need Data:URIs in IE7 and under

Key Concepts of MHTML

When you should use Base64 for images

Data URIs in CSS Cross-browser

Embedding Base64 Image Data into a Webpage

Aptimize for Realtime Spriting and converting bitmaps to MHTML/Data URIs

Base64 Encoded Images for Internet Explorer

Building MHTML Files from URLs

Data URI Examples for IE6/7

MHTML Test Messages

Short Summary of the MHTML Standard

Here’s a collection of CSS filters for targeting specific browsers with CSS when using HTML conditional comments or JavaScript detection is not an option:

Simple CSS Browser Detection

CSS Browser Hacks For Firefox, Opera, Safari & Internet Explorer

Browser-Specific CSS Hacks

More Browser-Specific CSS Hacks

CSS Browser Targeting

Cross-browser CSS Cheatsheet

The Triple-X hack for IE7

Lite Pacific Hack for Safari and IE7

Here’s a few references on ways to emulate fixed positioning in IE6 along with their caveats:

Fixed Positioning for Standards and Quirks Mode

IE6 Fixed Positioning Demo

Fixed Positioning Tutorial

Fixed Positioning Design Pattern

Here’s a collection of experiments using CSS to create various 2D and 3D shapes, images, and objects:

Arbitrary Lone Triangles

CSS Angles

Diagonal line in CSS

Drawing Diagonal Lines with CSS

A Diagonal Nav Rollover Effect with CSS

Diagonal Horizontal Green Menu

Drawing a Parrot with CSS

Triangles in CSS

Image Free Tooltip Pointers using Polygonal CSS

CSS Triangle Generator

Geometric Designs with CSS

Diagonal Lines in CSS

Simple Triangles in CSS

CSS Triangles

CSS Slanted Diagonal Borders

CSS Polygons

CSS Polygon Toolbox

CSS Digital Clock

CSS 3D Cube

CSS 3D House

CSS Keyboard

CSS Snooker Table

CSS Lamp

CSS Deck of Cards

CSS Legos

CSS Snowman

CSS TV

CSS Stars and Stripes Flag

CSS Union Jack Flag

CSS Transparent Five-Point Star

CSS Pencil

Here’s an excellent collection of tutorials and demos on creating rounded corners using HTML and CSS without graphics, SVG, HTML5 canvas, border-radius or JavaScript:

Image-Free CSS Styled Corners

Even More Image-Free CSS Styled Corners

Corner Shapes using CSS

How to Add Fluid Borders to Your Boxes with CSS

Rounded Corners using nothing but CSS

CSS Round Corners with Borders

Use Stripes and Inline Elements to Get Rounded Corners