Nah, I wouldn't. I just end up walking by various different departments as I wander through campus and think 'huh, what if I was doing that?'.. Then I can't help but think that I'd have better career options if I was doing this other, mythical course, and I end up hating myself.
Well, most of us spend at least some part of our lives wondering about roads not taken. Hell, I'm still wondering where I could've been if I'd gone into more creative pursuits - I love writing and have been paid for freelance writing work, but only ever to supplement my "real" studies in science, and I still wish I had more time for it.
My advice is this: if there is something that you would genuinely, passionately rather be doing instead of what you're doing now, then go for it. But if you're looking around at other courses simply because you're not entirely convinced you're where you're supposed to be, well, there's no guarantee that whatever else you try won't feel equally unfulfilling. That same brother of mine spent over five years finishing what should have been a three-year course because he kept switching subjects, and even then he never found something he truly enjoyed. I kept telling him that at the very least he should focus on doing well at the course he was in, to get the degree out of the way and open some more doors for himself. In the end, he finished an undergrad degree in god-only-knows-what, and once that was out of the way he felt freer to look for something he'd like. (He ended up getting into a JD course and falling in love with law.)
There are a lot of employers these days that'll take people with all kinds of undergraduate qualifications and train them on the job. Again, unless you really feel passionate about one particular field, the best thing you can do for yourself is earn a qualification and use that to move forward in your life rather than wasting too much time jumping from course to course.