Shark-Academy.com offers interactive (flash based) poker lessons. From handrankings to implied odds. We also offer a collection of entertaining poker videos.
Poker1.com is the home of Mike Caro's University of Poker and other online resources. It presents the "University" with 43 (!) lectures, test and strategy articles. There are also a lot of material on odds, rules, audio/video clips, tips and other. Also offers shop and forum. Very high quality and broad scope in the online strategy tutorials. Highly recommended!
The Poker Forum
Informational resource on poker, featuring forums, tournament info, rules, articles, book reviews and more. Especially the tournament section and articles on strategy and poker culture are worth checking. Nice original content, among other from John Vorhaus.
Coach Rounder is a revolutionizing poker software tool that serves as your own private poker coach. Upload your hand history and Coach Rounder returns detailed feedback on your strengths and weaknesses along with recommendations on what you can do to take your game to a new level. And best of all - Coach Rounder is available for free.
Texas Holdem Poker
Poker information resource and strategy guide. Features beginners guide, betting guide, odds, strategy advice, articles, forum, huge updated online tournaments database, newsletter, glossary and a link guide on poker and gambling. Good original content, quality site. Definitely recommended.