New Browser ofters the possibility to resize the Textarea. I like this Feature, but it is possible to resize it everywhere and as big as you want.

This Style doesn't allow a width more and less than 95%:
textarea{ height: 100px; width: 95%; max-width: 95%; min-width: 95%; }

You could also set a "max-height" attribut, so the user has borders in wich he can resize the textarea.

It would be nice if you implement it ;)