I have found a few extensions for Google Chrome to make life a bit easier when dealing with Bitcoins on the web. First of all I really like the idea behind this extension by Jonathan Waller called Bitcoin Microformats. It detects a Bitcoin link in the header of web pages and then shows a little icon in the address bar when a page supports this feature. The icon itself links to the Bitcoin address. The extension is open source so I added some features that I think were missing, the result is available here. I have added support for detecting "bitcoin:XXX"-style addresses, pages served as https, QR codes and more.
I hope some of these updates will be considered for the official extension, until then the extension can be installed manually from the link above.
Secondly, I made a small extension to be able to lookup Bitcoin addresses on blockchain.info through the context menu. This works both for addresses that are using the bitcoin URL scheme but also for plain text (by marking up the address text). It is available here.
What are some other useful apps and extensions?