I have the utmost admiration for all GLOs...but a few things stick out:
All of the D-9 for their LIFELONG commitment to service. What a great example they set for us all. AKA especially b/c their colors are the greatest.
Tri-Delt: I have honestly never met one I didn't like. I find their members, symbols & national organization to be very classy. I found out after I graduated from college that my grandmother was a Tri-Delt (she had not encouraged her children to go Greek because my grandfather didn't approve).
Chi O: For their strength-every chapter I've ever come into contact was a strong one...also, the Dallas Alum Chapter's Annual Philanthropy, "Chi Omega Christmas" always gets me in the Christmas spirit! (well, it used to, until I left the metroplex...*sniff*)
AGD: Silly, but I love their colors.
Lambda Chi Alpha: Always, always gentlemen. Love their colors, their symbols, their brotherhood, their badge. Always wanted to be a Li'l Crescent, but they outlawed li'l sisters at my school my Freshman year...oh well...at least I married one.
Alpha Tau Omega: 2 younger brothers are ATO's, and they have both grown into amazing men w/strong ties to their brotherhood. Every ATO I've ever met has strong leadership skills.