del.icio.us already have a list of bookmarklets for various browsers, and I started from there.

I have made two additions to the default bookmarklets: a faster way to enter an extended bookmark description, and the ability to add a predefined tag.

This is my generic "add to del.icio.us" bookmarklet, "add bookmark":

javascript:location.href='http://del.icio.us/new/martind?
	url='+encodeURIComponent(location.href)
	+'&title='+encodeURIComponent(document.title)
	+'&extended='+encodeURIComponent(getSelection())

Note the code after "extended=" -- this tells the browser to get the current text selection and use it for the "extended description" field. Before I bookmark a page I try to find a descriptive sentence on the page and select it, then click on the bookmarklet, and when del.icio.us loads the "new bookmark" form I usually only have to tweak the text a bit.

It's a really simple addition, but greatly enhances the experience -- I've already found browsing my bookmarks easier because of having good extended descriptions. Look at my del.icio.us page for some examples.

The second addition I use provides a default tag for new bookmarks. I really only use it for two tags: "revisit" and "later", which are my tags for pages that I either want to watch for changes, or visit at a later point when I have some spare time.

This is also pretty simple: "revisit"

javascript:location.href='http://del.icio.us/new/martind?
	url='+encodeURIComponent(location.href)
	+'&title='+encodeURIComponent(document.title)
	+'&extended='+encodeURIComponent(getSelection())+
	'&tags=revisit'

...so all that I did is add a default value for the "tags" parameter. Also a simple addition, but a great productivity enhancer. It now only takes two clicks to flag a page for later: clicking on the bookmarklet, and then clicking the "OK" button on the "new bookmark" form.

Note that I didn't "invent" these -- I first saw the text selection method somewhere on Jon Udell's site -- can't remember where, maybe in the del.icio.us screencast. And the default tag parameter is pretty obvious.

I guess it would also be easy to create a bookmarklet that doesn't even show the "new bookmark" form and simply adds the page to your account without requiring further user input, but I've found that I like to inspect the bookmark properties before I add it.