HighLine
High level library to deal with text user interfaces, build command line interfaces. Robust formatting has word wrap, paging, and list handling are possible. Handles validation rules for user input, implements menus easily. [Open source, GPL or Ruby License]
http://highline.rubyforge.org/

RUDL Library
Interfaces the Simple Directmedia Library to Ruby, giving it high speed graphics, sound, and input abilities. Links to related projects. [Open source, LGPL]
http://rudl.sourceforge.net/

XML::MetaGenerator
Collects user input, validates input and generates output in a number of ways based on the defined grammar.
http://search.cpan.org/~brujah/XML-MetaGenerator/

Visual Input Security
A source for dotNet controls and classes. Many are free and include source code.
http://www.peterblum.com/VAM/VisualInputSecurity.aspx

Apple Localization Tools: Chihui
Description Input methods for use with the Chinese Macintosh System 6.05 and above. Allows pinyin input in phrase instead of single character.
ftp://ftp.apple.com/developer/Tool_Chest/Localization_Tools/cihui.sit.hqx

Active Input Method Manager (AIMM)
Active Input Method Manager mirrors the Win32 Input Method Manager APIs to allow East Asian character input on non-East Asian versions of Microsoft Windows and Microsoft Windows NT 4.0.
http://msdn.microsoft.com/workshop/misc/AIMM/AIMM.asp

AntForm
Form-based input for Ant scripts. Provides tasks for creating input forms, wizards and menus. Supports a variety of widgets ranging from simple text to calendar controls.
http://antforms.sourceforge.net/

Input Routines
Fortran 90 module by Andy Stone that parses input lines into 'words', and routines that read a 'word' and translate it into a specified form, usually an integer or double-precision number. In conjunction with a simple CASE structure this provides a powerful and flexible method for organising data input. The package includes documentation, and an example program and data file as illustrations of the ways in which the module can be used to organise data. [gzipped tar file].
http://www-stone.ch.cam.ac.uk/pub/input.tar.gz

C Interfaces and Implementations
Explains the use of various interfaces such as string manipulation and data structure.
http://www.cs.princeton.edu/software/cii/

SederGraphics Interfaces
Offering four interfaces royalty free in Adobe Photoshop 5.5 format, with all original layers.
http://www.sedergraphics.com/