QUOTE(sianeth @ Aug 25 2008, 05:12 PM)

Wow, what isn't there to see/do.
From my short and sweet experiences in South East Asia, I recommend getting into the countryside in the North of Thailand and trying a trek - or maybe up in Sapa, Vietnam. Do some diving down the coast of Thailand (Koh Tao or the Simian Islands) and hit up some of the fabulous beaches (Koh Phi Phi, Raileh Beach, Krabi etc). In Malaysia try and get over to either the Perhentian Islands or Pulau Tioman down by Vietnam, which is absolutely beautiful - the reefs and snorkelling there are incredible.
Not too sure about cambodia, phillipines, vietnam, laos etc although I'm sure there's some awesome stuff up there and you'll have a cracking time.
This is an excellent list.
For Neil - going on your own - sounds great to me.
Budget - hmmm, I am sure someone has asked a similar question - search through the forums and see if you can find it.
Possible additions to the list - Malaysian Borneo. Climbing Mt Kinabalu, visit Sepilok Orangutan sanctuary, travelling up the rivers to the long houses in Sarawak or to Mulu National Park.
Angkor Wat in Cambodia.
Halong Bay in Vietnam
Inle Lake in Myanmar
The list could go on for ever