A dedication to Randy Pausch from his "Building Virtual Worlds" class, Fall 2005. Randy Pausch (www.randypausch.com) is a virtual reality pioneer, human-computer interaction researcher, co-founder of CMU's Entertainment Technology Center (www.etc.cmu.edu), and creator of the Alice (www.alice.org) software project. Other videos by Randy, including downloadable versions of this and other talks, can be found at www.cs.virginia.edu/robins/Randy Less