Wouldn't it be cool if there were a collection of bookmarklets that
let you munge-up your websites? For example, I use Bloglines.com multiple times a
day to read through all a shitload of weblogs and other syndication
enabled sites.
One particularly annoying thing due to it being a web application is
that if one post is using a <pre> tag (for example, to show off
some code), or the text can't wrap (because there's a long string of
non-whitespaces characters, for example, in a URL), all of the text in
will go long, requiring me to use the right-left scroll bar. The
<pre> problem happens on blogs.sun.com almost every day,
while the whitespace/URL problem happens on Jeff Nolan's site
almost everyday.
This is a minor annoyance, as the fix is just to extend the content
frame. However, it'd be nice if there was a feature to pop the content
pane up into it's own window. I'm pretty sure you could write a
bookmarklet to do this: just have it open up a new window, and copy
graft the DOM tree of the posts into it.
Building on that, there's all sorts of customizations you could do
to other web applications. Since everything is open (by virtue of
being in HTML and JavaScript), all you have to do is reverse engineer
how the site works.