These are my tried and tested ones (after a few useless things that ended up being thrown away).
Small for a dwarf, medium for a Syrian and they have rabbit sized ones too
Rosewood (Small Animal Toys) Boredom Breaker Hamster Chew Tube
Brilliant buy! Hide in it, climb on it eat it, chew it, lie upside down in it and rip it
Small for dwarf and syrian hamsters (our syrian chewed the door a bit bigger). Large for rabbits. Last year they did a coconut topped one as well for Christmas - also a good buy.
Naturals Carrot Cottage for Small Animals
Nice little bridge
Boredom Breaker Small Rainbow Play Bridge for Hamsters Gerbils & Mice
I don't have one of these but they are fun - too small for a syrian
Classic Hideouts Hamster Town T.V.
Excellent buy. Hide treats on it - hamster has to stretch and pull to get them. I ring the bell on it when it's dinner time! I actually replaced the little ring at the bottom with a large ring (just a plain key ring, ring) as I was worried about feet getting caught in the small ring. Small ring prob ok for a dwarf though.
Small 'N' Furry Treat 'k' Bob for Small Animals
I got Charlie one of these for Christmas last year, for out of cage time. It's quite big but is somewhere to go and hide when out of the cage and can also be good for transporting him from room to room (but have to watch he doesn't try and jump out!) Also have to watch them for chewing the fleece.
Classic Snuggle Up Rat Slipper Toy
We have one of these. I tend to set it up on top of the bed. Sometimes on the floor.
Supreme Hamster Fort
Charlie polishes these off in one night
Boredom Breaker Treats Rodent Mini Sticks for Rodents Hamsters Mice
Nice sized treats
Boredom Breaker Treats Little Hearts for Rabbits Guinea Pigs Hamsters
Our Syrian likes these
Boredom Breaker Treats Dandelion Sticks Rabbits Hamsters Mice Rodents
These can be chewed for weeks and weeks. Quite big - about 3 or 4". I prefer them from Amazon as it was fresher. May have been a one-off but the one from Viovet looked a bit old and Charlie wouldn't eat it. The one from Amazon he adored.
Boredom Breaker Treats Nibble Woodroll-Carrot for Rabbits and Rodents
And these mini Antos toothbrushes
Antos Cerea Toothbrushes Dog Chews
I can also recommend these treats from elsewhere!
Charlie goes potty for one of these
Nibble Wood for Small Pets at zooplus: JR Farm Dandelion Root
These are popular too and last for ages - biggish bag
Great Deals on Small Pet Snacks at Zooplus: JR Farm Oat Bites
And these for an extra special treat
http://www.amazon.co.uk/Boredom-Brea...shrimp+cookies