As RCF moves towards the Condor batch system I thought I'd compile a list of some useful commands here.  The ones with a * next to them should be run from the node on which you submitted your jobs.  The full Condor 6.8.3 manual is at

http://www.cs.wisc.edu/condor/manual/v6.8.3/index.html

condor_q -submitter username -format "%d" ClusterId -format "  %d" JobStatus -format "   %s\n" Cmd shows the job id,  status, and command for all of your jobs.  1==Idle, 2==Running for Status.  I use something like this because the default output of condor_q truncates the command at 80 characters and prevents you from seeing the actually scheduler job ID associated with the Condor job.  I'll work on improving this command, but this is what I've got for now.
 
condor_status -submitters shows the numbers of running/idle/held jobs for each user on all machines

condor_status -constraint 'RemoteUser == "username@bnl.gov"' lists the machines on which your jobs are currently running

* condor_release username releases all of your held jobs back into the pending pool

* condor_rm username removes all of your jobs submitted from this machine