As my contribution to Ada Lovelace Day 2010 I would like to mention Emma Jane Hogbin.
Emma is an Ubuntu Member, published author, documentation evangelist, conference organiser, Drupal theming expert, tireless conference presenter, and many more things as well.
Her enthusiasm is infectious, and her passion for solving problems for people is admirable. She is a constant source of inspiration to me, and that continues even as she branches out in to new things.
(Hat tip for the title to the ever excellent Sharrow)