There is already the personal nodelet. If you have it turned on, a list of your bookmarked nodes is visible with every pageview. The node currently being viewed can be added with a single click. Some shortcomings of the personal nodelet are that it does not allow any kind of reordering or renaming (as far as I know).

If that is a problem, you can use your scratchpad instead; a link to add a node to the scratchpad is also found in the personal nodelet. The advantage of the scratchpad is that you can edit it, and make it public if you desire. The disadvantage is that unlike the personal nodelet, it isn't included with every pageview. Still, one of the two should be capable of providing the functionality you desire.