Need a modem? Go down to CompUSA and for $20 ($19.99, actually), you can pick up a 56Kbps modem card that also can send and receive faxes. It's completely unremarkable (except perhaps for the question of why you'd even need a modem in this age of wireless access points and built-in Ethernet ports).

But set the time machine to 1986, when dinosaurs walked the Earth - and Network World began. Back then, Racal-Vadic's 9.6Kbps modem had a list price of $1,200; Fastcomm's $1,100. Or you could try your luck on a US Robotics Courier HST 9.6Kbps modem for only $750. Not fast enough? Telebyte offered a 19.2Kbps modem - at $3,500. 56Kbps? Hah! That's what WAN backbones used.

When it comes to network gear, Moore's Law seems to have done pretty well over the past 20 years - prices have tumbled even as performance has skyrocketed. To see by how much, we tried to compare what $20 would buy you today - and what it would have gotten you 20 years ago.

Today, for about $20, you can buy a 10/100Mbps network interface card (NIC) (if you really want to splurge, add another $10 for a 1Gbps model). In 1986? Forget about it! Digital sold the equivalent of an NIC for $500. Connecting Ethernet segments back then might run you $3,800 for a 5Mbps Ungermann-Bass repeater or $8,000 for a 10Mbps DEC LAN Bridge 100.

Applitek sold Ethernet bridges for $13,000 each (but they did packet filtering). Today, you can get a D-Link DWL-G810 108Mbps (wireless) Ethernet Bridge for $120 or so.

Storage is another network technology that has seen almost unbelievable changes. Today, $20 would buy you about 36GB of storage (based on a 250GB Western Digital hard drive recently advertised for $139 at CompUSA). In 1986, one Usenet post marveled that somebody was selling 71MB Micropolis hard drives (with retrieval times of 30 millisecs) for $1,250 apiece. "I bought one before he was able to get sane, and I would recommend you do the same," the poster wrote. So if it were possible to divide that hard drive, for $20, you'd get a little more than 1MB of storage (which today wouldn't be enough to hold a single photo from your basic digital camera). For more permanent storage, you could buy an ISI optical-disk system, which used write-once CD-ROMs, for $3,000.