HCSB Study Bible - this is my favorite Bible translation and study Bible. First Baptist Moreland gives these as gifts and if you fix my car, I'll give you one. The study notes aren't as thorough as the NIV Study Bible, but are outstanding at providing the text in the overall biblical narrative.
ESV Study Bible - this study Bible contains so much info, I still haven't finished learning what's in it. The articles in the back are books in themselves. Even if you don't use the ESV (I don't), you still need to own this resource.
NIV Study Bible - I was saved and raised on this Bible. I believe it has the best study notes of all, it doesn't have the articles and features as the first two. This has been the #1 study Bible for 20 years! I especially love and use the cross reference system.
NKJV Study Bible - a rising star - Its really doesn't have anything the first 3 don't already have. Uses the Strong's numbering system if you use it.
Apologetics Study Bible - not in the Big 3 - but an awesome resource to own. More people want to borrow this Bible from me than any other. The articles and twisted Scripture references share insights to how people misuse God's Word. Parents should give this to their college students.
Need a Bible for your phone? YouVersion Bible App - I use this for my iPhone and have been impressed with all the translations and ease of use - plus it's free!
This came out last month...The Gaither Homecoming Bible - wow, I want someone to buy this for me...