Easy, there is several similar proposals, e.g. Automatic Coin Mixing Idea.

Any happy-customer-stories yet?

That idea crossed my mind too but I rejected it right away, like, I don't want to think about that.

Tiny update:
Nicer URLs for item links: https://www.bitmit.net/zh-cn/item/10103-gourmet-pizza-oven-1000w
Login possible via Email address or username

Yes, it is not obvious at all that it is a tag associated with the address, it looks like it is just an ad being run by your site.  Perhaps you should add a label saying something like "owner-supplied address tag".  I am sure you can find a better wording

You Can. Here is a real life use case:

The users "mralbi" has had 600 BTC stolen by a Trojan on his/her PC (https://bitcointalk.org/index.php?topic=126024.0). The address the funds were sent to is http://blockchain.info/address/1Q3KFL7Z1BTpUboDaU6Qj3t9xCXWpzNntS. On the Taint analysis you can see there are two addresses tagged: "nyana" and Mt.Gox" http://blockchain.info/taint/1Q3KFL7Z1BTpUboDaU6Qj3t9xCXWpzNntS. Theoretically the owners of these tags could be contacted and offered a bounty to provide any information they can on the address 1Q3KFL7Z1BTpUboDaU6Qj3t9xCXWpzNntS. Perhaps they have sent a transaction to that address before. This is just the beginnings of what might be possible in future but does stress the importance of keeping addresses isolated from one another if anonymity is desired.

For a few bucks I can see it as a courtesy, why not. As OP said, help someone get his first BTC. But otherwise, many people do not want to sell their BTC.

Hey, cool, I'm happy

For now a tag submission page is available at http://blockchain.info/tags. Also for a bit of geeky fun I indexed the addresses contained in signatures from bitcointalk.org example: http://blockchain.info/address/1H4sGgNSRvRuiUsbucsQBNFWhZcLnL2KW1

It doesn't include up or down voting as the tags in this context probably serve a slightly different purpose than your original idea giszmo. Which was to allow people to tag addresses as belonging to scammers, add comments etc? While I could see this being useful in some situations it has the danger of morphing into a blacklist which in my opinion is a bad idea all round.

This could be an interesting plot for a novel. The silent killer. Send him bitcoins for his cash.. or else...

Quizás te sirva esto: https://bitcointalk.org/index.php?topic=118299.0

First, I'd consider that (1) I don't solicit such anonymous transactions, (2) I'm always short on bitcoins and need more, and (3) I keep my mailing address VERY private, and would immediately be suspicious if such an envelope arrived.

Now, assuming that the only things in the envelope were cash and a bitcoin address, I'd be stuck. There's no way to return the money. And if anyone is watching me surreptitiously, I'd have a hard time imagining doing the transaction would be seen as worse than just keeping the money (for now at least.)

So, yes, I'd do the transaction. It would take a little while, as I'd use the money to buy more bitcoins first, rather than send them mine. And I'd charge them quite a bit to compensate for the hassle and annoyance (refer to points 1, 2 and 3 above). But I'd probably take the time to also send them enough micro-transactions to form a message, something to the effect of "dont do this again" or "charging 50% next time."

Really? Where?