Ask HN: Should I go back and finish my CS degree?

I attended university for a degree in CS right out of high school but never finished, completing about the first 2 years. After dropping out and wandering around for a bit I eventually went and did a 3 year college Systems Analyst program. I graduated with great grades and have since had a couple jobs working as a software developer and am currently working for a large financial institution. I am fairly happy with my job but I feel like I am kind of stuck doing the same web application/SOA web service type work. I would really like to work on some more interesting problems where I get to actually use some cool algorithms. I have been considering some options for completing my bachelors degree in CS, but I am just not sure if it is something that I really need or not in order to move to where I want to be in my career. I spent a lot of time on my while at college sort of trying to play catch-up on the stuff that I missed not finishing my CS degree. I feel I have a fairly strong background in CS despite not finishing; I have written neural networks and parser generators for fun in my spare time and have a fairly good understanding of a lot of the basic CS concepts such as data structures/algorithms, time complexity, graph theory etc. I currently do a lot of web related stuff but I have done a fair amount of C/C++ as well. If anything I feel my weakest point is math. I know basic calculus and linear algebra but nothing advanced really. My strongest skill is probably software engineering in general (design patterns and whatnot). Is there more that I would have learned from finishing my degree that is essential? Do you really need that piece of paper, or can just having enough experience and the knowledge itself get you the job of your dreams?