multiple cygwin terminals without running X
I found Poderosa to be a good solution for running multiple Cygwin terminals within a tabbed window whilst doing Rails development. 
As Poderosa is a Windows app it was easier to set up than the various X Window solutions suggested, such as MRXVT.
You can split the screen if you like which I do when I need to keep an eye on both my development and test log files.