Chrome: Webclip is a lightweight Chrome extension that clips the web-based text to a scratchpad in your Google Docs account.
Webclip is no frills: you install it, you authorise it to access your Google Docs account, and you click the paperclip icon on your toolbar when you want to clip text. Clipped text is dumped into a document labelled "webclips" along with the name of the page, the date, and a link back to the source. Currently clipping is limited to text and all clips are saved in the master scratchpad document.
Webclip is a free extension and works wherever Google Chrome does.