a: First 'Select All' and 'Copy' the piece of text below:

javascript:location.href='http://www.bananalbum.com/m/?album='+location.href;

b: Add a bookmark for *this* page.
c: Go to your bookmarks and edit the one you've just created, remove the link and 'Paste' the text you've copied a second ago.

Now... when visiting a BananAlbum which is not compatible with the mobile viewer, just click the 'mobile viewer for BananAlbum' bookmark and you'll be able to browse through the images!