TPF and CFCs
I read somewhere that the TPF would be able to detect chlorofluorocarbons on other planets, which would be pretty diagnostic for intelligent life. Other than that, TPF doesn't have much chance of detecting INTELLIGENT life. The time window in which an ETI is producing CFCs is probably very short, a century or two, so the chance of actually finding anything is vanishingly small.
I sure hope TPF survives the coming budget crunch. Both it and SETI deserve funding.