Personally I just use a photocopier - each time I fill a page up I put it on the office photocopier and file the page (complete with copies of scribbled notes, crossings out, official stamps, instructors signatures...) in a file which I then keep somewhere different to the logbook (most of us have a home and place of work which does that easily enough).
Nowadays a scanner or digital camera should do the same thing of course, but they didn't really exist when I started flying! (Eek, showing my age).
G