Are any of these honorifics still in use today? 愚, 鄙, 敝, 卑, 窃, 仆, 婢, 妾, 在下, 贱妾, 小人, 小女, 草民, 民女, 奴才, 奴婢, 奴家
Betty's answer is great. Here's some complement: Since almost every Chinese can understand these words, we use them in spoken lang occasionally, usually expressing some kind of mood or feelings.

For example, if someone adopts an arrogant and impolite attitude to you, you can use one of the honorifics to express a scatching satire to strike back. 

And sometimes we use 草民 or some other worse words like 屁民 to deliver the helplessness about the status of common people in mainland. (There is even a word made for this: shitizen)

Also, there's something interesting too. We can call the company we working for 敝司, just in order to express our sense of humour. This may not be easy understood by a foreigner.