Microsoft’s Live Labs has a preview release of an enhanced browser for Windows Mobile 5 (or, presuably, 6) Pocket PCs and Smartphones.
Deepfish Technology Preview: Enhanced Browsing for Windows Mobile
The website says Deepfish is currently only available by invite only to a small number of beta users. However, download versions for both the Pocket PC and Smartphone appears to proceed without any issues. You can see a video demo of it on Microsoft’s On10.net website.
EXCLUSIVE VIDEO: New mobile web browser – Deepfish!