I've been avidly reading these forums to figure out how to get the most bang for my buck on a trip around the world. Thanks to the insights here I've splurged just a bit extra in order to get a business class ticket, by cutting its price massively from what it would've cost straight out of Japan, where I live.

A few things that saved me a lot of money:
- starting in Johannesburg (this one was massive)
- ending in Dakar instead of Joburg
- skipping Asia completely
- avoiding London (huge airport taxes)
- trying different codeshares for same flight

Oddly I found that a lot of LAN flights stop existing after April 3.

I'm still tweaking it but would be great to get any input anybody might have. So far I have:
JNB-SYD-AKL-SCL-LIM-EZE-GRU-MIA-MEX-surface-CUN-DFW-YVR-JFK-HEL-MXP-MAD-DKR

I have no particular need to go to DFW or MIA but there were no direct flights so thought I'd check them out.

Again, thanks for the amazing advice.