While doing a tour of diy shops I noticed toolstation are doing bits for RNLI including recycling envelopes for mobile phones, satnavs, mp3 players, digital cameras, portable games consoles & ink cartridges. "For every items that is successfully recycled The Recycling Factory will make a donation on your behalf to RNLI" No idea what donation but I have a couple of redundant mobis & always get empty ink carts that will hopefully add a few quid to RNLI coffers.
If you don't have a toolstation near you, you can order extra envelopes from therecyclingfactory.com/rnli or tel:0800 0910696