Mireth Technology has released NetShred X 4.0, the latest version of its Internet track eraser that erases cache, history and email trash. Version 4.0 adds: support for more Web browsers — Firefox 2, iCab 3, Shiira 2; Support for more mail programs — Thunderbird 1.5; and support for erasing site passwords for Firefox 2. NetShred X is priced starting at US$24.95.