While some of the approaches mentioned below do work to some extent (TRIZ, etc.), they won't really make you "inventive". Personally I think they're all gimmicks (although to be fair they are gimmicks that work). I think what you really want is to "become" an inventive person instead of trying to force invent stuff. Read this book for starters: http://www.amazon.com/Where-Good-Ideas-Come-From/dp/15944853...

remote Ph.D. is a bad idea; the Ph.D. experience is isolating enough as-is, and pushing it remotely will exacerbate those problems. plus, innovation often happens in serendipitous in-person encounters in the hallway, lounge, and lab with students, professors, and research staff incidentally bumping into one another. see:

http://www.amazon.com/Where-Good-Ideas-Come-From/dp/15944853...

I believe it is very important to keep a notebook in your pocket. I write down every idea even if it is a "dumb" idea. There is potential for every idea to build into a grander idea.

I recommend reading the book "Where good ideas come from".

http://www.amazon.com/Where-Good-Ideas-Come-From/dp/15944853...

3. What about Where Good Ideas Come From by Steven Johnson (http://www.amazon.com/Where-Good-Ideas-Come-From/dp/15944853...)?