Am Mittwoch, den 27.05.2009, 14:27 -0700 schrieb Robin H. Johnson:
> On Wed, May 27, 2009 at 09:00:54PM +0100, Roy Bamford wrote:
> > Is this a spam outburst that will blow over ?
> No, it's been growing in intensity for the last 6 months.
> 
> > How will visually imparied users subscribe ?
> > If that is still possible, I'm not against such a move.
> I specifically stated recaptcha [1], as it includes an audio recognition
> task for blind users, as well as rate limiting abuse attempts.
> 
> 1. http://recaptcha.net/
> 

An alternative (which works quiet well with my blog):
have an empty css-hidden input field in the form and check for it being
empty when submitting the form. Bots will fill it out since they ignore
CSS mostly.
Advantage: it's hidden for all users and for those where it isn't
(Screen-Readers) you can add a normally hidden description stating this
is a spam-catching-field intentionally left blank.

-- 
Tiziano Müller
Gentoo Linux Developer, Council Member
Areas of responsibility:
  Samba, PostgreSQL, CPP, Python, sysadmin, GLEP Editor
E-Mail   : dev-zero@g.o
GnuPG FP : F327 283A E769 2E36 18D5  4DE2 1B05 6A63 AE9C 1E30