I have been thinking of posting on this
As some have already commented borrowing abroad is essentially a currency play (although buying an asset in Australia might be seen as a bet on $AUD).
First you need to have a multi currency facility.
You can borrow foriegn currency loans in Australia from St George bank. Not sure of the terms.
http://www.stgeorge.com.au/mortgage/home_loans/stgeorge_home_loans/foreign_currency.asp?orc=personal
As many have pointed out you can borrow from HSBC/CITIBANK in singapore/Hong Kong.
Here is a link to LloydsTSB HK
http://www.lloydstsb.com.hk/product/mortgage_tc.html
Most of the products are pretty similar.
There are also a number of private banks who can also arrange this for you.
E.G.
http://www.kaupthingsingers.co.im/Pages/1406
There are also a lot of brokers out there who could help out. Savilles private finance in the UK are one.
These currency mortgages clearly fluctuate. You have to be able to cope with these changes (i.e. your debt rising). However most will limit the LTV to say 75% and then only allow you a further 10% buffer in case of a currency crash. I.E. if you debt grows to 85% LTV the lending bank will reconvert it back into the currency of the assets.
This at least provides a sort of stop loss.
If you are fearful of managing the currency trades you can have a currency manager look after it for you. They will manage the currency switches for you. They have three aims when doing this 1. Reduce your interest. 2. Reduce your debt. 3. Tax advantages. The biggest currency manager of multi currency mortgages in the UK has been doing this for a while. Here is their website.
http://www.ecugroup.com/
They usually charge a performance fee for such services. This fee will usually come out of any profits made.
Alternatively;
Finally there are currency managers who have done away with the mortgage part and just synthetically create the trades that moving your mortgage debt would create. This save you the hassle of actually having to remortgage and being subject to the sometime restrictive terms of a multi currency mortgage (i.e. you can keep your current loan with your current mortgage lender).
How does this work in practise? Well you might set up an account with a CFD or spread betting firm with them to manage your currency account. You deposit in some cash (usually 5% margin) they simulate moving the debt. E.G. $50,000 would allow them to place trades that simulate having a mortgage debt of $1,000,000. The aim being to make money in the same way as a multicurrency mortgage.
The advantage being that you do not have to move your mortgage around. Also you can do it with a smaller margin (e.g. 5%) and they can break this up into smaller parcels than just simply moving all of it from Sterling to US$ to $AUD. The can split it into ten different trades and have only half of your capital exposed at any one time. They can also leverage it a lost higher than 1:20.
Here is a link to Multicurrency Mortgage
http://www.multicurrencymortgages.com/
Currently Multicurrency Mortgage only offer this service to UK nationals but I'm sure anyone who offers a managed currency trade account could probably put this together for an individual. Multicurrency Mortgage also offer it as a spread bet rather than a currency trade as this does not attract tax in the UK (I don't know the tax status of this in Australia).
Obviously these are all speculative and higher risk strategies for investors. Leveraging the carry trade as well as leveraging in the property market may be a bit too dangerous for most! I think that there are ways to manage the risk though I have yet to take the plunge and go for a multicurrency mortgage (despite earnings in a number of currencies).
This isn't advise and I haven't got a multicurrency mortgage.