GrepClipse is an easy way to filter an Eclipse console's content through a regularexpression as you'll do it on a *nix console through the commands grep -n <regexpr> <currentConsoleContent> followed by tail -nf <newConsoleContent> | grep <regexpr> helping the analysis of logs during the execution of a process.
This is a simple Java front-end for the UNIX grep. It lets you search file contents also if you are not familiar with the command line or the regularexpression syntax.