Probably one of the easiest ways is by using NetMon or some similar network sniffer package. NetMon and Sniffer Pro can both understand and translate TDS packets (Tabular Data Stream - What Sybase and SQL Server both use to communicate between client and server). Typically though there are a lot of special characters in a TDS packet, but you can see the data going back and forth with respect to character fields and queries. If the transmission, you shouldn't be able to decipher any of it with the naked eye.
K. Brian Kelley
bkelley@sqlservercentral.com
http://www.sqlservercentral.com/columnists/bkelley/
K. Brian Kelley
@kbriankelley