In many developing nations you can save a lot even from a $1k salary. If not, dedicate some time to freelancing, either locally or via elance/odesk. Shoot let's say for $40k per hour and do 2-3 hours per evening of that, plus some time on weekends. 20 hours = $400 per week, $1600 per month additional. Do that for a year and you will have money to live on saved funds for 1,5 years.
Depending on which country you live in, taxes can be a real pain and will only leave you with a small bit of your salary. Not to mention transportation could eat up a lot your otherwise "free time" in the evenings. :(
I do agree that freelancing would definitely give some nice extra income but only if you're disciplined enough to find time for it.
Most developed nations have all kinds of barriers and quotas in place to make it difficult for aliens to fill jobs that might otherwise be filled by citizens.
Sometimes the right connections, company sponsorship, etc. can get you in; but if you're imagining just flying to the UK or wherever and getting a job, that's not possible. Even if a company there wants to hire you and is willing to jump through legal hoops it still may not be possible.
You don't have to work in a developed nation to work with developed nation clients.
Try and target yourself to those clients and avoid the local clients like a plague. It has been my experience that if you want to break into more profitable territory you need to break away from local clients completely.
