Makepp, a build program that has a number of features that allow for reliable builds and simpler build files, is a drop-in replacement for GNU make. It supports almost all of the syntax that GNU make supports, and can be used with makefiles produced by utilities such as automake. It is called makepp (or make++) because it was designed with special support for C++, which has since been extended to other languages like Swig or embedded SQL. Some features that makepp adds to make are: greatly improved handling of builds that involve multiple makefiles (recursive make is no longer necessary); automatic scanning for include files; rebuilds triggered if build command changes; checksum-based signature methods for reliable builds, smart enough to ignore whitespace or comment changes; extensibility through Perl programming (within your makefile); repositories (automatically importing files from another tree); and build caches (not recompiling identically what a user of the same cache already did).
ack is a tool like grep, optimized for programmers. Designed for programmers with large heterogeneous trees of source code, ack is written purely in portable Perl and takes advantage of the power of Perl's regular expressions. It searches entire trees by default while ignoring Subversion, Git, and other VCS directories and other files which aren't your source code. It uses Perl regular expressions to find just what you want.
nrun is a tool that runs a single command or script on multiple target servers synchronously. ncopy will copy a file or directory to multiple target servers. The underlying remote access mechanism is interchangeable, and currently supports ssh, nsh, rsh, and local execution modes. The return code and all command output is logged.
PerlShare is a DropBox drop-in to create your own private file sharing "cloud". It consists of two parts; a client and a server. The server part lets you configure a Linux machine to accept PerlShare clients. PerlShare behaves a lot like DropBox. On collisions, for example, it creates conflicted copies. The workhorse for synchronization is Unison, a very reliable piece of software from Pascal Bach.