A list of some of the Google Chrome Extensions I have found useful:
AdBlock - Great for blocking all those ads
Browser Button for AdBlock - Adds a button to AdBlock, some like, some don't
Tynt Blocker - Allows the user to prevent Tynt.com from recording copy/paste events from sites that use Tynt's tracer script
Chrome Pig - Google mail checker, Mouse gestures, Allow right click and select text and image, Dictionary search, Open URL in IE browser, Screenshot webpage, Change desktop wallpaper, Fill login form, Youtube lyrics search and repeat play, Change webpage style and block flash/image, Translate webpage, Docs viewer and more
The Tracktor - Amazon Price Tracker - Access The Tracktor Amazon price data from within Chrome
Session Buddy - Flexible Chrome Session Management
Forecastfox Weather - View current conditions, 7-day forecast, maps and severe weather alerts
WOT - Web of Trust is a safe browsing tool, which warns you about risky sites that cheat customers, deliver malware or send spam. AFter you install it, just click the 'next' box, then close the 'account' box. You don't need to create an account.
Click&Clean - Deletes your browsing history, typed URLs, Flash cookies
FlashBlock - FlashBlock for Chrome. Block them all, or be selective with the embedded whitelist manager
Tab Menu - Select, close, rearrange, and search your tabs from a toolbar menu
Webpage Screenshot - Fast&Simple solution to Save & Share & Print & Edit screenshots of any webpage. Capture to PNG/JPG drawing tools, and sharing features
Google Mail Checker Plus - Gives a popup like Outlook when new email arrives; works with Google Apps
SearchPreview for Google - preview images (thumbnails) to your Google search results
Email this page (by Google) - adds an email button to the toolbar which allows you to email the page link using your default mail client or Gmail
RePlurk Chrome - After installation, a "RePlurk" button will be added inside the Plurk message box. Clicking on the "RePlurk" to repost the Plurk you're viewing.
PlurkMate - adds a button to your browser toolbar. It displays the number of unread messages in your Plurk timeline and update every 3 minutes.
RPlurkSmileys - More Plurk Smiles
Download the Latest Google Chrome Dev channel build
Using this post as a way to create a collection, until Google creates "collections" like we have at Mozilla; My collection at Mozilla: Nethead's Recommended Addons for Firefox.