Chameleons are awesome! I have a Yemens Chameleon myself!!
However. He is the best thing in my life.. i am NEVER donig the 'chameleon thing' again!
If it is your first reptile... i really recommend you not getting a chameleon. They arent easy at all, also whilst the Pygmy Chams are really cute, chameleons are seriously a 'hands off' pet and dont much like being handled at all.
The correct humidity, temperature, UV, Basking light etc. Believe me, small vivariums for chams are seriously hard work! Trying to fit on a UV bulb, a basking kight unit and either finding time to spray them every day without fail (as they only drink droplets!) or another expensive bit of kit like a mister.
Not to mention the viv, the light units etc for both heat and UV sources, a digital thermometer and hygrometer for the temperature and humidity readings.
I shouldnt think they live long at all! Would dpend on species and i'd have to double check but the bigger yemens only live 3-5 years tops (my boy is 3
) yeah... about 3 years unless you find someone selling them as babies as they are generally wild caught adults and dont live so long.
Just a few ideas though but you are going to need some serious research on keeping any of the smaller species. Reptile Forums UK would be best place!
But just thinking of another species or two for you...
How about Frogs? Dendrobate arrow frogs? Definately not handleable (without latex gloves on!) but then... neither are pygmy chameleons. Im thinking of going down that route eventually!
Lygodactylus species:
http
/www.google.co.uk/search?tbm=isch&hl=en&source=hp&biw=1052&bih=635&q=lygodactylus&gbv=2&oq=lygodac&aq=1&aqi=g8g-S2&aql=&gs_l=img.1.1.0l8j0i24l2.812.3911.0.5301.7.6.0.1.1.0.317.1475.1j0j4j1.6.0...0.0.w3zJFMh3Y9A
The Electric Blues (L. williamsii) is what im planning to keep a breedng group of eventually. Saving up though as even at 3cm or so... they go for about £90 each and i want one male, three females LOL. However there are lots of similar Lygodactylus species but not so bright. Google Yellow Headed Lygodactylus.
Phelsuma species of Day Geckos. There are a lot of species around, might be some small enough? Phelsuma klemmeri look awesome and dont need much space at all, you could easily keep 3-4 in that space
http
/www.geckosunlimited.com/community/gecko-care-sheets/18789-phelsuma-klemmeri.html
and last one i can think of is:
Stenodactylus, instead of rainforest set up, it would be a small desert settup! Seen gorgeous settups with little caves, sand and cacti and rocks etc.
Cant for life of me remember which species is the commonly available one but they are cute as heck! About 1-2" and scamper about fast and bask on pebbles under the heat.
Maybe some more ideas?
http
/www.google.co.uk/search?hl=en&q=tiny+stenodactylus+species&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&biw=1052&bih=635&wrapid=tlif133780441583510&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=hUa9T9UHzZnRBebW8Do