Signs? Consider these verses:

    “And God said, Let there be lights in the firmament of the heaven  to divide the day from the night; and *let them be for signs*, and for seasons and for days, and years.        Genesis 1:14

“God bore witness by signs and wonders and various miracles and by gifts of the Holy Spirit distributed according to his own will.” Heb 2:4

Jer 32:20  Who hast set signs and wonders in the land of Egypt even until this day, and in Israel, and amongst men, and hast made thee a name as at this day. 

“Many signs and wonders were done among the people by the hands of the apostles” Acts 5:12

"In the last days, God says ...I will show wonders in the heaven above and signs on the earth below, blood and fire and billows of smoke."  (Acts 2:17 -19)

The following verse is from Book Four of the Prophet Esdras (aka Ezra)
     "For just as with everything that has occurred in the world, the beginning is evident [obvious], and the end manifest in wonders and mighty works, and the end in requital (compensation) and in signs."

Jesus himself said, "If they (his disciples) were to keep silence, I tell you the very stones would cry out." (Luke 19:40).  This could be a prophecy and explanation of hundreds of statues and icons of Jesus and Mary around the world weeping human tears and tears of human blood...

Speaking of healings and exorcisms:
Mar 16:17  And these signs shall follow them that believe: In my name they shall cast out devils. They shall speak with new tongues.
Mar 16:18  They shall take up serpents: and if they shall drink any deadly thing, it shall not hurt them. They shall lay their hand upon the sick: and they shall recover.
Mar 16:19  And the Lord Jesus, after he had spoken to them, was taken up into heaven and sitteth on the right hand of God.
Read "The Real Exorcist Story" from the homepage of PDT Signs for one the most fascinating exorcisms and wherein that power lies.
For healings consider that for any person to be proclaimed a saint they must have at least 3 profound miraculous healings attributed to them.  
For not being harmed by deadly poison consider the eight priests who survived a nuclear blast and the intense radiation, in "The Hiroshima 8" from the homepage.

There are signs all around us again that we will see signs such has not been seen since the time of Moses:
Exo 34:10  The Lord answered: I will make a covenant in the sight of all, I will do signs such as were never seen upon the earth, nor in any nations; that this people, in the midst of whom thou art, may see the terrible work of the Lord which I will do.
 

Luk 21:11  And there shall be great earthquakes in divers places and pestilences and famines and terrors from heaven: and there shall be great signs. Luk 21:25  And there shall be signs in the sun and in the moon and in the stars; and upon the earth distress of nations, by reason of the confusion of the roaring of the sea, and of the waves: 
-Read "One Step" or go to www.jmmccanneyscience.com or www.planetx2003.com

Num 14:11  And the Lord said to Moses: How long will this people detract me? how long will they not believe me for all the signs that I have wrought before them?
Jer 10:2  Thus saith the Lord: Learn not according to the ways of the Gentiles: and be not afraid of the signs of heaven, which the heathens fear

...and for prophecy:

Joel 2:28

And it shall come to pass afterward, that I will pour out my spirit upon all flesh; and your sons and your daughters shall prophesy, your old men shall dream dreams, your young men shall see visions:

1 Corinthians 14:1

Follow after charity, and desire spiritual gifts, but rather that ye may prophesy.

1 Corinthians 14:22

Wherefore tongues are for a sign, not to them that believe, but to them that believe not: but prophesying serveth not for them that believe not, but for them which believe.

1 Corinthians 14:39

Wherefore, brethren, covet to prophesy, and forbid not to speak with tongues.

1 Thessalonians 5:20

Despise not prophesyings.

Romans 12:6

And having gifts differing according to the grace that was given to us, whether prophecy, let us prophesy according to the proportion of our faith;

1 Corinthians 12:10

To another the working of miracles; to another prophecy; to another discerning of spirits; to another divers kinds of tongues; to another the interpretation of tongues:

Acts 2:18

And on my servants and on my handmaidens I will pour out in those days of my Spirit; and they shall prophesy:

Revelation 1:3

Blessed is he that readeth, and they that hear the words of the prophecy, and keep the things that are written therein: for the time is at hand.

Revelation 19:10

And I fell down before his feet to worship him. And he saith unto me, See thou do it not: I am a fellow-servant with thee and with thy brethren that hold the testimony of Jesus: worship God; for the testimony of Jesus is the spirit of prophecy."