Are you a runner or a walker? Is it your way of keeping fit and seeing the great outdoors? You could kill another bird (so to speak) with that same stone, if you entered an organised run or walk and raised sponsorship for the RWF while doing it.
Entries are being taken at present for the London Marathon, the Edinburgh Marathon and many more. There's a list here of the many, many runs that take place up and down the UK, so there's bound to be one near you. http://www.marathonrunnersdiary.com/races/uk-marathon-list.php
Will you help us to help rabbits? Not quite 'Run, Rabbit, Run', more 'Help rabbits...run!'