Timeliner– create timelines and timemaps using Google Spreadsheets (this tool is also available under the name TimeMapper – it is somewhat unclear as to the difference between Timeliner and TimeMapper)
Timeline.js – an open-source tool that enables you to build visually-rich interactive timelines (hosted version)
Viewshare – a free platform for generating and customizing views (interactive maps, timelines, facets, tag clouds) that allow users to experience digital collections
Timetoast – create timelines and share them on the web
MyHistro – Hosted tool to create timelines (requires signup for a free account)
GeoCommons – A public community and set of tools to access, visualize and analyze data with compelling map visualizations.
Kartograph – A simple and lightweight framework for creating beautiful, interactive vector maps
Mapbox – A web platform for hosting custom designed map tiles and a set of open source tools to produce them.
Modest Maps – a small, extensible, and free library for designers and developers who want to use interactive maps in their own projects.
WorldMap – low barrier open source platform to explore, visualize, edit, collaborate with, and publish geospatial information.
Ushahidi – online platform to collect and display information geospatially
DataWrangler – interactive tool for data cleaning and transformation
OpenRefine – desktop tool for cleaning and transforming data
Mr. Data Converter – web application that converts Excel data into one of several web-friendly formats, including HTML, JSON and XML
Data Science Toolkit – Variety of data tools including street addresses to coordinates, file to text, coordinates to political areas, geographic names (countries, city, region) to coordinates, IP address to coordinates, HTML to text, text to people, etc.
JSONView – a Firefox extension that helps you view JSON documents in the browser.
dataset-tracking – plugin for the Mantis (http://www.mantisbt.org/) issue-tracker designed to support work-flows around “data publication” in research settings. The plugin enables editors to use Mantis’s issue-tracking features to coordinate work on cleaning datasets, aligning datasets to appropriate standards, and documenting datasets for publication.
Entypo Pictogram Suite – a set of 250+ carefully crafted pictograms. The package contains an icon font — OpenType, TrueType and @font-face — EPS, PDF and PSD files. All released for free under the license CC BY-SA 3.0.
Divshot – Bootstrap-based mockup interface builder for Web apps
Gemicon – handcrafted icon set (600 icons in sizes 16, 32, 64px)