Generators for synthetic (spatio-temporal) datasets

Spatial Data Generator by Yannis Theodoridis Group@Unipi. 
For point or rectangular (static) objects. Available athttp://www.rtreeportal.org/software/SpatialDataGenerator.zip

GSTD (Generating Spatio-Temporal Datasets) by Yannis Theodoridis and Mario Nascimento [TSN99, TN00, PT00]. 
For point or rectangular moving objects The original version assumed unrestricted motion in the workspace while a more recent version introduced restrictions as an infrastructure of stationery objects. 
Available at http://www.rtreeportal.org/software/gstd.tar.gz

Generator for network-based moving objects by Thomas Brinkhoff [Bri00, Bri02].
For moving points in road networks. The driving application is the field of traffic telematics.
Available at http://www.fhoow.de/institute/iapg/personen/brinkhoff/generator/

OPORTO Generator by J.-M. Saglio and Jose Moreira [SM01].
For point and region moving objects, motivated by the concept of fishing ships (ships are attracted by shoals of fish, fishes are attracted by plankton areas, and so on).
Available at http://www-inf.enst.fr/~saglio/etudes/oporto/

G-TERD (Generator for Time-Evolving Regional Data) by Yannis Manolopoulos' group [TVM02]. 
For complex regional objects, with their motion influenced by other moving or static objects.
Available at http://delab.csd.auth.gr/stdbs/g-terd.html