You might also want to try:
http://www.phoenixdatasolutions.co.uk/seisvu.htmIt's also a free SEGY Viewer by Pheonix Data Solution, now taken over by Fugro.
The offer a simplified version of SEISVU with most of the functionality of the full version disabled. But it still offers the ability to view the seismic data (colour display and conventional black and white traces). Also, you can view all the file header information (the EBCDIC, binary, reel header and all the trace headers) There is also a fun little gimmick that let's you listen to your seismic!
You'll need to fill in a short form and then should be directed to the download page.