Yep. Here’s the evidence.

SAN FRANCISCO — The high-tech industry has been working itself into paroxysms of excitement lately over an idea that is not exactly new: tablet computers.

Quietly, several high-tech companies are lining up to deliver versions of these keyboard-free, touch-screen portable machines in the next few months. Industry watchers have their eye on Apple in particular to sell such a device by early next year.

Tablets have been around in various forms for two decades, thus far delivering little other than memorable failure. Nonetheless, the new batch of devices has gripped the imagination of tech executives, bloggers and gadget hounds, who are projecting their wildest dreams onto these literal blank slates.

In these visions, tablets will save the newspaper and book publishing industries, present another way to watch television and movies, play video games, and offer a visually rich way to enjoy the Web and the expanding world of mobile applications.

“Desktops, laptops — we already know how those work,” said Brian Lam, editorial director of the popular gadget site Gizmodo, which reports and hypothesizes almost daily about these devices. Tablets, he said, “are one of the last few mysteries left.”