Now it's possible:
http://www.publicdebt.ustreas.gov/ols/olshome.htm
These bonds may be cashed within ~6 months (~5, if you buy them shortly before the end of any given month).
Saar
[This message has been edited by Saar (edited 11-17-2001).]
[This message has been edited by Saar (edited 11-17-2001).]