If you’ve studied New Testament Greek, you know who Daniel Wallace is (not to be confused with the author, angler, and alligator wrestler, the rheumatologist, or the Star Wars geek). His Greek Grammar Beyond the Basics (also available from Logos Bible Software) is an essential resource for intermediate Greek students. Not only does it provide an excellent overview of the grammar and syntax of the Greek NT, but it also offers some fresh perspectives on difficult passages. I don’t always agree with Wallace’s exegesis, but I find his views helpful and thought provoking.
Wallace has contributed online through the Pen and Parchment blog and the Center for the Study of New Testament Manuscripts blog, but now he has his own blog, which you can find at DanielBWallace.com. I’d encourage you to check it out and subscribe to the RSS feed (or if RSS still mystifies you, sign up for the email or bookmark the site).