Connect to a SQL Server on the network.
Select some records.
Now unplug your network cable / disconnect from wireless.
In the result set, right-click, Quick Export, Linked Query to an Excel Instance, Excel Linked Query...
A background process is started, which of course won't be able to finish while you're disconnected, so re-connect to the network.
Expected: that either the background process would finish or would at least error out.
Actual: Background process runs forever.
Expected: that I could click the stop button beside the background process to stop it.
Actual: Stop button does nothing with this particular background process.
Eventual Result: After about 3 hours, Toad Eventually crashed.