你是什麼東西??

[doumeizhen]

And for fear of roddy's reprimand javascript:emoticon(':wink:') I hope this fits,

but in Shanghai, they use 葱 (cong, onion) to ask where you come from.

I think you would use it like this:

你是什么葱？

What onion are you?

They said it was because onions spring from a central bulb, but it might also be cute because it sounds like 从。

[Quest]

well, should I add Cantonese

你係乜水？

What water are you?

[sherman]

It is bad if someone speaks to you '你是什么东西？'=>You are something.

While it is worse if you are told that “你不是东西”.=>You are not anything.

这是汉语中很有意思的两句话，无论用肯定或否定的方式说，都是骂人。

[ala]

In Shanghainese we could say: 侬算啥物事？ (noN seu sa mezzi?)

kind of means the same as Mandarin 你算什么东西？

Usually we just say: 啥物事俄。。。 saving our breath in contempt. Less verbal exchange means more acidity.

Unfortunately, we don't have 侬是啥物事？ (hearing that makes me think: "What thing are you?") It makes no sense in Shanghainese. But we do have 伊勿是东西。 as well as 侬算什么东西？(obviously loaned wholesale from Mandarin). 东西 is usually used in Shanghainese only for the negative connotation (usually referring only people); while 物事 just means any thing or object.

Unexciting? Shanghainese makes it up with many many other colorful terms and phrases.