I feel like may be overly praising Southeast Asia (as this is the 3rd recommendation for it I've given today on Thorntree), but it is a truely amazing place. I would not be worried at all about traveling alone as a female in SE Aisa, but I would be cautious at Night. You could jet around the region pretty well in a month (I did it in December/January 09/10 before living there last May through August). You can get a super cheap flight on Air Aisa from London to Kuala Lumpur, Malaysia, and then it has dirt cheap connections to pretty much anywhere you'd possibly want to go throughout the region. It will be warm in August, but not deathly so. You'll get used to the increase in temperature and humidity within a week or so, then it'll be smooth sailing (unless you do a Singaporean or Malaysian bus as they are crazy airconditioned). If you stay at Youth Hostels, you'll most likely meet other who are traveling, and have people to pal around with a bit - making things a bit safer and less lonely. Overall, Asia is pretty safe as long as you use common sense and don't go crazy places by yourself at night. Singapore, however, has basically no crime at all. If you do end up going, invest in the SE Asia on a shoestring Lonely Planet. I've used mine so much that it's falling apart and I have chunks of it memorized (what it has to say about the Singaporean Merlion is hillarious), and I've given it away as a gift before.
