MODERATOR NOTE: Post 1 through 5 were taken from other threads on the forum.
I'm going to answer my own question again:
There is a special investment visa. It's called a "Special Investor's Resident Visa", quoted from the immigration website:
This appears to only be an option for investing in the private sector:
I am not sure if this covers corporate bonds. However, I think investing in corporate bonds would count as "investing capital in various economic activities". That's just a completely uneducated opinion though. This would require a discussion with the immigration office/embassy/lawyer.