Suggestions for expl3

The following packages have something in common with the package expl3. The packages are ordered in decreasing similarity.

Package l3regex: Regular expression facilities for LaTeX
Package l3docstrip: Strip documentation in LaTeX3 source
Package l3kernel: LaTeX3 programming conventions
Package l3kernel-dev: Development pre-release of l3kernel
Package l3keys2e: LaTeX2ε option processing using LaTeX3 keys
Package xargs: Define commands with many optional arguments
Package etl: Expandable token list operations
Package afterpage: Execute command after the next page break
Package somedefs: Save loading all of another package
Package trace: Make sensible use of TeX tracing in LaTeX
Package xspace: Define commands that appear not to eat spaces
Package zhlipsum: Chinese dummy text
Package xfp: Interface to the LaTeX3 floating point unit
Package xparse: A generic document command parser
Package xtemplate: A high-level interface for declaring document commands
Package functional: An intuitive functional programming interface for LaTeX2
Package l3packages: High-level LaTeX3 concepts
Package showkeys: Show label, ref, cite and bib keys
Package l3experimental: Experimental LaTeX3 concepts
Package amsbsy: Produce bold math symbols (AMS-LaTeX)
Package array: Extending the array and tabular environments
Package helvet: Load Helvetica, scaled
Package pifont: Access to PostScript standard Symbol and Dingbats fonts
Package rawfonts: Low level font compatibility mode for LaTeX
Package shellesc: Unified shell escape interface for LaTeX
Package psnfss: Font support for common PostScript fonts
Package structuredlog: Report files opened and closed in the log, including nesting level
Package forloop: Iteration in LaTeX
Package xcoffins: Rich boxed material for LaTeX 3
Package xfrac: Split-level fractions
Package hawkdraw: Draw vector graphics using l3draw with a simple syntax