Some great suggestions above, many of which I read!
I'd add:
The Discomfort Zone -- great insights from a very amusing, honest life coach.
PickTheBrain | Smarter Self Improvement -- for "Smarter self improvement" -- good practical advice on all aspects of personal development.
Dumb Little Man -- practical, wide ranging topics, and definitely the potential to give you some life changing ideas.
Anywired — work online, work anywhere, live free. -- great blog if you want to change the way you work. And I really like the way Skellie writes, always something insightful!
Oh, and feel free to check out mine,
The Office Diet -- I don't know if it's changed anyone's life yet, but I know from my own experience that successful weight-loss (and maintainance of that loss) truly is life changing (I wrote a guest post about it for
I will change your life . com , a blog which Parthon mentioned above, a couple of weeks ago).
Best,
Ali