GIS data and viewer:
ArcGIS Explorer: ArcGIS Explorer gives you an easy way to explore, visualize, and share GIS information. ArcGIS Explorer is free
Free Viewer (ArcGIS): Easily visualize and share spatial information
Free GIS data: Free GIS, Remote Sensing, Spatial and Hydrology Data
Hydro/GIS data: Hydro1k data for Asia which include DEM, slope, flow direction and streams data
NOAA GIS data: FREE digital elevation, globes and global relief images
WebGIS (ORNL): The ORNL DAAC WebGIS includes a number of land cover, biophysical, elevation, and geopolitical layers
SRTM elevation data: Shuttle Radar Topography Mission 90m elevation data for the entire world (data with other spatial resolution are also available)
Satellite/Remote sensing data:
Land cover data: Global land cover data from FAO Land and Water division
Landsat data: FREE global orthorectified Landsat satellite data for three epochs: 1970s, 1990s, and 2000s
MODIS satellite data: FREE global scale MODIS satellite data
Remote sensing tutorials: How to use this tutorial and a synopsis of the principles
and applications of remote sensing
Vegetation data: Global scale satellite derived vegetation data download for FREE
Climate data:
Global (IPCC) models: Global climate models from Intergovernmental Panel on Climate Change
Precipitation data: Land based precipitation data from NOAA website - observational and gridded data
Rainfall data: Global Flood Alert System - rainfall and flood status around the world
Groundwater quality and arsenic data:
Arsenic data (Bangladesh): Groundwater arsenic data for Bangladesh collected by British Geological Survey and Bangladesh Department of Public Health
Google Earth and other GIS links:
Flying over Dhaka: A flight over Dhaka City at an altitude about 2 km from south to north of the city (link opens the KMZ file on Google Earth)