Cuch makes a good point, it is difficult, but that is in some ways is a good thing.
There may be a seriously good market in GPU tech centred around CUDA with banking experience. It may be quite soon.
I make the unintuitive claim that it being hard is actually good because to earn a good living with a skill, it has to have some barrier to entry, and the best is that only you and the right sized set of people have the talent to do it.
Occasionally the barrier is due to law protecting a profession or the cost of gaining the skill. That's less good because the law can be changed, and occasionally technology drops the cost hard.
Of course it must not be too hard, else the lack of skilled workers to do it will deter people from using it.
You need the barrier, else as soon as the price goes up, people rush to learn it, drive the price down, and since they have invested in this skill and will hang around, the price will keep on going down for a while.
In my my view this is the market for Java skills.
To be more lucrative you need people with money who want this work done, and who will make money from your activity, and since people are competitive, they will pay more for an edge than more boring cost saving activities that offer equivalent returns.
Also there is a subtle point, not covered well in the literature, which is that employers must feel that the skill 'deserves' higher pay, typically because they see it as more difficult.
It is tempting to bring Java in again since it's virtue is ease of use, but a better example is Excel VBA. Most employers sees it as trivial so won't pay good money, then spend hours bitching about the hours they've lost because their spreadsheets don't work.
So CUDA has good barriers, and employers with deep pockets.