What are some gift ideas to promote the prevention of water pollution?

Roxanne asked: If my college club is promoting water pollution prevention, what are some good gift ideas to give away to our attendees?Content supplied by Articlesbase.com

Challenge: How to get people to not bring gifts to a birthday celebration *without* directly asking?

WWDD? asked: The person whose birthday it is doesn’t like surprises of any sort, so gifts aren’t a great idea. The attendees are people who usually bring gifts, so it’s not assuming.
Homer S: *I* would do that. However, the people asking me to write the invitations requested that I don’t, so that’s what I have [...]