Hey Guys,
I've been a line guy for 4 years now, and I've been in the aviation community slightly longer... you could consider me one of them there 'Whippersnapper pilots that's still wet behind the ears'...
During my service at the airport, I've learned a few things that I feel every pilot should know. Much to my surprise however, quite a few of them don't! So... here goes nothing:
* When taxiing into an airport, the line guy will more than likely point your aircraft in the direction of the wind, or in a direction that results in the least amount of tailwind. This is a standard and common procedure.
* When parking at an FBO, if the ramp is full of aircraft and a line guy is nowhere to be found... park your aircraft in the same direction as the rest of the aircraft! (They're all pointing the same way for a reason) You have no idea how often I encounter this issue! The only exception would be during a frontal change where your pointing your aircraft into the wind.
* When a line guy parks your aircraft, and seems to possess a fair bit of knowledge, don't treat him like an idiot. That's just not cool. Example:
Line Guy: "Hi, Welcome to ____. What can I do for you today? By the way, that's a great-looking 1956 172. I love those straight-tails. Does this still have the O-300?"
Pilot: "Yes. It still has the O-300. Have you ever fueled a Cessna 172 before? I need it topped off with 100 Low Lead Av-Gas."
- That's just not cool guys... I do understand when pilots watch the line guys fuel up their aircraft - I encourage it! Also, I understand specifying 100LL versus 80 or 100 Octane fuel.... just don't talk down to us. It's important to understand that although line guys are underpaid, they're not ignorant. (Some special cases apply)
Here's a cool tip: Did you know that you can actually save money by talking to the line guys? I know a particular 135 operator that used to spend $10.00 on pizza for the line department when he'd come in. You may think that's asinine... but it always worked in his favor. All applicable fuel discounts would apply, and for some unknown reason, his landing and ramp fees would be waived. During the winter months, he'd even get a free heated hangar for the day.
Of course, buying the line department probably doesn't work at these larger FBO's... but it definitely works at the smaller Mom 'n Pop locations. Try it sometime - At the very least, they'll always remember you and treat you with care in the future.
* If it's a slow day and the frequencies aren't congested, thank the approach controllers for their help before you sign off and wish the person in the tower a great day. It really means a lot to those guys. A controllers job is monotonous enough, and they constantly deal with impersonal pilots, they start thinking of us as numbers rather than people. A quick thank-you and have a great day may actually make their day.

I'm sure other people have some great useful information regarding Hints, Tips, Tricks for the aviation world. (Other than completely ignoring everything that I just said!
) Please share your experiences with the rest of us.
~Adam