Someone mentioned waif-thin eyebrows. I'm sorry, but I've been seeing even THINNER eyebrows over the past 5 years than I did in the 90's. I've seen WAY too many times the rediculous style of women plucking out ALL their eyebrows and penciling them in (and they'll regret it once the style is over because their eyebrows won't grow back). It's as if looking like a drag queen has become something admirable or something. Female RuPauls!
I've seen the 90's version of punk coming back, 90's-style men's jeans (baggy but tapered at the bottom) coming back, 90's haircuts (women's inverted bobs, men's mushroom cuts, manic-panic colors on bleached hair), collarless shirts or shirts with minimal collars.
The gangster extra-baggy jeans that show off boxer shorts hasn't ever went away.