Pastor John Piper has been preaching for more than a decade that we should not "dismiss the so-called sign-gifts to quickly.” He is not merely suggesting that we be “open but cautious” (as would Wayne Grudem) but rather to "eagerly desire and cry out to God for an impartation of the Holy Spirit and all His gifts."
Although he does not describe himself as a Charismatic or Pentecostal, he very clearly supports a “continuationist position” (as would Sovereign Grace Ministries). Back in Feruary of 91', Pastor Piper had this to say:
I [believe] that ‘signs and wonders’ and all the spiritual gifts of 1 Corinthians 12:8-10 are valid for today and should be ‘earnestly desired’ (1 Corinthians 14:1) for the edification of the church and the spread of the Gospel . . . I want to argue . . . that the New Testament teaches that spiritual gifts (including the more obviously supernatural or revelatory ones like prophecy and tongues) will continue until Jesus comes. The use of such gifts (miracles, faith, healings, prophecy, etc.) give rise to what may sometimes be called ‘signs and wonders’ . . . There is no text in the New Testament that teaches the cessation of these gifts. But more important than this silence is the text that explicitly teaches their continuance until Jesus comes, namely, 1 Corinthians 13:8-12 . . . verse 10 can be paraphrased, ‘When Christ returns, the imperfect will pass away.’ And since ‘the imperfect’ refers to spiritual gifts like prophecy and knowledge and tongues, we may paraphrase further, ‘When Christ returns, then prophecy and knowledge and tongues will pass away from Signs and Wonders, Then and Now, emphasis added).
A year before this (90') Pastor Piper preached that, I confess that as far as I can remember there has been no question in all my preaching ministry that has caused me more heart-wrenching uncertainty. I sit at my desk with my head in my hands and plead with the Lord, on the one hand, 'Oh, Lord, if there is a wind of true, Biblical, spiritual power blowing in our day with signs and wonders and healing and prophecy, forbid that I should stand in the way! . . . Make me the leader you want me to be for the greatest blessing of this church, and the greatest missionary effectiveness.' But then, on the other hand I pray, 'Oh, Lord, forbid that we should lose our Biblical bearings; forbid that we become trendy or faddish and begin to substitute the sand of experience for the rock of revealed truth. Show us the fullness of the power of the gospel, Lord, and keep us from preoccupation with secondary things, no matter how spectacular (Are Signs and Wonders for today?; this is part of a fourteen-part sermon series on the gifts entitled, “Are Signs and Wonders for Today?”).
Recently (8/20/06) he summarized his position again in a sermon entitled, By Signs and Wonders (emphasis added): Should we be expecting the same miraculous confirmations of our witnessing [evangelism] today? My answer is yes, but not in the same measure that the apostles experienced this miraculous power . . . God intends to bless his word and his people with miracles in our day — extraordinary works of divine power that go beyond the laws of nature . . . when the Lord Jesus returns to heaven and the apostles have laid the foundation of the church in the New Testament and are taken off the scene, I think what we have is not a de-supernatualized religion. Not at all! The Holy Spirit has been poured out, and he is still fully capable of doing signs and wonders . . . [and] not to ask for them seems to me to be more secularistic and naturalistic than biblical.
For more on this, check out the following article by Jeff Purswell, Empowered by the Spirit: Room for Differing Views.