Thanking big spending customers

I was wondering whether or not anyone sends out e-mails to customers who spend a lot - say 100k or more - at their shop thanking them for their custom and saying they hope they shop at their shop again.

While I've never actually sent out such e-mails I have received a few over the last couple of months from shops where I restock a lot of stuff from.

So opinions? Will it encourage further custom or just annoy?

As a "power shopper" I am easily annoyed by anything that slows me down, but that's not who our customers are. It seems like the people who shop in malls might be looking for some social interaction - judging from all the neomails and neofriend requests we get from them. So, yeah, it might be a good thing.

Here's something I liked doing for about a year, and it got me good feedback:
I'd sort my Sales Tracker data by customer each month, and any repeat customers would get a thank you note and a Pretty Bouquet (30NP). I wouldn't say it successfully created customer loyalty or anything, but it was fun to think so ....

I'd be interested in what you decide. Maybe we could make it a mall-wide practice to send out thanks.

I don't do anything systematic. Sometimes around holidays I send big customers a seasonal gift or too. I don't know that it gets me any more business but it just seems like a nice goodwill gesture.

I thank my big spenders -- the really big ones -- by sending them a little note and a Thanks Card (~1000 np). These guys are usually the ones who spend 200k+ by buying a big map set or a World Challenge set (400k-600k in one shopping trip!). I don't think it's brought any of them back (kind of one off things), but made me feel good and if it brings one back once, its all worthwhile.