The 1891 Slander of Women Act is still on the statute book in 2009, as I discovered when I was trawling through the UK Statute Law Database - a fascinating pursuit. It's a very short Act, which states:
Words spoken and published which impute unchastity or adultery to any woman or girl shall not require special damage to render them actionable.
Provided always, that in any action for words spoken and made actionable by this Act, a plaintiff shall not recover more costs than damages, unless the judge shall certify that there was reasonable ground for bringing the action. (see here)
I'm no lawyer, but I think this means that women do not have to have suffered financial loss as a result of the insults in order to sue the slanderer. However, any compensation (costs) the woman receives as a result of going to court, will not exceed any financial damage she has suffered.
If anybody would like to slander me or any other woman, I advise you to go to Scotland to do so - the Act does not apply there!