在 Simon Willison 的 Greasemonkey as a lightweight intermediary 這篇文章裡提到：

In The architecture of intermediation, Jon Udell discusses the need for a mechanism for a high-level tool for adding custom features to web applications. In Jon’s case, he wants to add a private bookmarks feature to del.icio.us. Jon thought about using a web proxy to intercept and modify del.icio.us pages, but ruled it out as too low-level.

沒錯，為了在 del.icio.us 增加新功能，有些天位大長輩就會去弄 web proxy，然後修改 proxy 的程式碼，透過 proxy 修改 del.icio.us 的 web html…