Patterns and Pattern Languages are used to describe best practices, good designs, and capture experience for reuse.
An Introduction to Process Patterns - This white paper introduces the reader to the concept of process patterns, reusable building blocks from which an organization may tailor an object-oriented software process.
Cetus Links -- Architecture and Design: Patterns - This site provides a wealth of information on patterns. Links are provided to tutorials, FAQs, literature, organizations, conferences, software tools, and ftp archives.
Handbook of Software Architecture - The primary goal of the Handbook of Software Architecture is to fill this void in software engineering by codifying the architecture of a large collection of interesting software-intensive systems, presenting them in a manner that exposes their essential patterns and that permits comparisons across domains and architectural styles. Reflecting on his work on patterns, Christopher Alexander notes that he and his colleagues "made observations, looked to see what worked, studied it, tried to distill out the essentials, and wrote them down." This approach is at the core of all good science.
Hillside.Net Patterns Library - Design Patterns describe common and well-known designs for doing things. People have discovered there are many repetitive themes in designs. A recognized central source of information on patterns is found at this page.