With more than one hamster to find presents for and them being particular about what type of toys they like, I actually made them little treat parcels and filled them with their favourite food and treats. The intention was that they'd chew through the paper to get to the treats inside.
To show you what I mean, here's the video of Lady May with hers:
Another idea which I saw during my last visit to Vectis was a treat kebab:
Treat k Bob on Sale | Free UK Delivery | PetPlanet.co.uk
I bought one the other day for Jessie and have swapped some of the wooden chews (which I know she'll ignore) for other treats. It keeps her occupied and she likes rattling the little bell on the end. Rosewood sell a similar product without the bell if you're worried about Sweep chewing the bell.