Annalisa,

Just across the water from you in Wan Chai, there're a few laundries to that do it by the pound. Underwear too. My best experience was a little place that wanted 40 or 45 HKD for up to 9 lbs. Was done by 5pm.

I can't remember the street it was on, but if you like, I can dig out the picture I took of it. It was on a side street near the intersection of Johnston and Hennessey, the end that was nearer Causeway Bay.

Clothing came out folded, dry, nicely scented and super clean.

In fact, it "restored" some gruesome underwear that I was going to throw out in favour of some new pairs I bought at Uniqlo. [I'll spare you the details of what "gruesome" means.] Don't know how they did it. (Powerful commercial-grade washing machines perhaps?)