Here's what I did...
Using a similar naming system, my husband has proposed that we change the internet connections from each student name to the animal names!
I imagine this would work not only for people with a number of visitors coming through their house but simply as a way of identifying each child or teenagers space as well!
The book of stickers set me back $2 and the coaster $2.50. Having a few extra animals up my sleeve would be handy if we were to have more students than the three we currently host - but if nothing else, it gives you a back up if one goes missing or gets ruined somehow. If you have a printer you could always print off a load of the same animal pictures and glue them on instead of using stickers. That way you could size them and get exactly what you need.
Quick cheap and best of all, easy for everyone!
Green-ness: 3/5 for using some items I ready had but lose marks for buying new stuff...
Frugal-ness: 5/5 for spending less than $5 on this project
Time cost: about 1/2 an hour
Skill level: cutting and pasting as usual!
Fun -ness: Great fun and I think the students like the animal motif!