JotSpot
Jotspot - a Wiki plus forms, e-mail + RSS integration, optional XHTML markup, file attachments. Unfortunately, it's a service (ASP), not a software you could install on your own server...
How JotSpot Is Different: "Using a simple scripting markup, JotSpot allows you to create Forms. Forms bring structure to your wiki pages. Forms define fields such as "text," "date," "number", etc. And, pages can contain both structured and unstructured text."