If you've been feeling a little left out lately, what with all this talk about cyberspace, internets and info-highways, it's time to get a grip.

Today, the veteran rock band Aerosmith offers the first-ever computer-released song, available only at your desk, provided you have a PC (with sound card) and a subscription to the on-line service CompuServe.

The 3-minute, 14-second song, Head First, will not be sold, or released to radio stations. How long it will be available on ComuServe is still being decided.

The band and its record label, Geffen, call the not-for-profit release an experiment.

To hear it, just sign on to CompuServe and type "Go Aerosmith."Downloading from digital to audio form should take 60 to 90 minutes, depending on modem speed, CompuServe reps say. CompuServe is dropping its usual connect-time charges for members who want to listen in.

Described as a typical Aerosmith rocker, the song was recorded in 1993 during the sessions for Get A Grip, but was not included on that album.

So what will all this mean? Probably not much, initially.

It's unrealistic to expect fans to spend hours downloading audio material. But technology moves fast, and Geffen wants to be ready when the process is streamlined.

Purchasing music through on-line services is one of several alternative music delivery systems taking shape. Local cable outlets, phone companies and in-store recording booths where buyers create their own customized albums, also will play roles.

Geffen has been connecting with fans on line for a while, offering them sound-bites of new songs, tour schedules, interviews with artists, and upcoming album information.

CompuServe subscribers who need assistance downloading Head First can call 1-800-524-3388. Ask for representative 615.