Orangutans
We visited a NP in Kumai, Kalimantan, Indonesia where wild orangutans are being closely monitored (and fed) by NP rangers. For the complete story, check out the Meet the Orangutans post.
Proboscis Monkeys

Macaques
Macaques are common throughout SE Asia. They hang around many tourist attractions hoping to get fed (and can sometimes get very aggressive when they aren’t!)
To read more about the time a cheeky monkey stole my strawberries, head to this post.
Langurs
Railay Beach, Thailand