DeltaMUD is a MUD server based on enhancements to the original CircleMUD bpl12 source code and is thus bound to the legal terms contained within the CircleMUD and DikuMUD license agreements. The goal of this project is to provide an enhanced, memory optimized, and SQL-based version of the original CircleMUD.
Deliver is a program for reliable and flexible local mail delivery. It's a perfect adjunct to your mail transport agent of choice (such as Sendmail or qmail). You can use it to kill spam, drop messages from specific senders, add a [LISTNAME] prefix to the subjects of messages that are delivered through mailing lists, and lots more.
DeleGate is a multi-purpose application level gateway or proxy server that mediates communication of various protocols, applying cache and conversion for mediated data, controlling access from clients, and routing toward servers. It translates protocols between clients and servers, converting between IPv4 and IPv6, applying SSL (TLS) to arbitrary protocols, merging several servers into a single server view with aliasing and filtering. It can be used as a simple origin server for some protocols (HTTP, FTP, and NNTP).
DECO (Dynamic Encapsulator of C++ Objects) converts DC++, essentially C++ with extensions for "dynamic encapsulation," into standard C++. Used as-is, DECO can only convert the simplest form of interfaces (types) and implementations to C++, so although it could be interesting, its most practical use is probably to provide a start for parsing C++. Note that template and exception handling support is incomplete in the parser, since DC++ did not make use of these features.
The DECnet for Linux project aims to provide the kernel-level socket layer and a set of applications to allow Linux systems to participate in a DECnet phase IV network. It currently has an application library (suitable for building DECnet functionality into X11R6), file and terminal access.