Do not give a Christmas present to any SB.  We have a rule here that says "no honey, no sugar" for a reason.  If you feel like you must do something to please your SB, take her shopping after she blows you and swallows an extra large load and use her sugar to buy her a watch, shoes, purse, or some other useless bling. Then let her realize she could have used that cash to pay the January rent or power bill.  
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Ok, small gifts are fine; a Starbucks Card for $30, gift certificates for dinner for 2 at Sizzler, maybe an iTunes card so she can download some crappy hood rap music on her phone. Knock yourself out with one or two of these baubles. But don't even think of parting with hundreds of dollars that normally comes after you get laid.

Give her some small gifts that show you actually care and have paid attention to her likes and dislikes.  I gave one SB a nice kaleidoscope on her BD, because she had mentioned she liked them. Cost all of $25 but was actually quite a cool thing and she soooo loved it, and was really amazed that I remembered.  Another one I found a Tshirt that said "real unicorns have curves" and had a picture of a rhino on it.  She absolutely loved it since I've been calling her my Unicorn which she likes a lot.  Another I bought a pint of Grey Goose, her favorite spirit. What I'm saying is that these things cost me around $25 bucks and created major good will and appreciation.  No more is needed.

of a small trinket that was a gold replica of Hilton Head Island.  Didn't cost that much (but you guys are just cheap  lol), and when I gave it to her, her first comment was "but where's the chain?" So I guess I will out-cheap you guys at Christmas.

My most important and significant SB and I will be spending our third Christmas together and you're damn right I'm getting her a present.  It will come back to me a hundred fold; it always does!

but she could use it on her BF or other SDs. So may be a Starbucks card.

Nicest jewelry she ever owned - but we’d been exclusive for 6 months.   2nd xmas, I paid for her airfare for trip to her native country.   But that was after 2 years as exclusive to one another and we are at a point where we go bareback and do quit a lot together, so she’s really like a kept mistress girlfriend at this point.

I gave my ATF 2 pairs of thongs in her favorite college logo.  She’s in school but favors one of the arch rivals of my alma mater