placing next/previous page navigation in sidebar

I am feeling a bit stupid... but I would really like to place a link to the previous/next page in the sidebars.

I've looked for a plugin; up till now I haven't find one.
I've tried to copy the <?php next_posts_link('&laquo; Previous Entries') ?>
in a text-widget, but that didn't work.

Is there another way to create this?

My website is http://cpost.nl/online-magazine-curacao

The next/previous-link is at the bottom of the post. The most readers of this online magazine are users with a laptop. These links will not be visible for them.
I do not want to place the next/previous-link on top, because the top of the website is already stuffed with too much 'information'.

So I would like to place a image of some kind of arrow with a link to the next/previous post in the sidebars. Any one any suggestions?