So, against the advice of a few MNers (and arguably my better judgement), I went and bought a "trendy" modern-ish rain bonnet (one of these - www.instagram.com/thebonnit/?hl=en). Got it in the post on Friday and now summoning up the courage to wear it if it rains on my way into work.
While this may have worked for Rihanna, still kind of wondering if I can carry it off on the tube, so in a complete abdication of responsibility, thought I'd let Mumsnet decide...