I've had items jump from $30 to over $300 in the last few minutes and I've had items sit at a low level with no last minute bidding.
That is the great thing about Ebay ( sorry for saying that ) but I have had auctions a few years ago that where high end items, and I was sweating it out watching it with 4-5 minutes to go at 200.00 and it was well worth over a thousand,... and then in the last few minutes it sold for 1850.00 (In about 1 minute of bidding left)... that is fun to see!!!