Light/Ultralight Top/Bottom Loader Backpack?

Check out Golite.com. Look at their Mountain/Trekking Packs.

Some are frameless; some have internal frames. Some top-loaders only. At least one, the Galaxy, IIRC (discontinued for '07 i think i just read, but still available) has top and bottom loading capability.

Granite Gear makes a front loader (internal frame; L, not UL) called, i think it's the Nimbus Latitude, or is it the Nimbus Ozone – well, at any rate, it's one of those two. So does Six Moon Designs (UL pack – no frame; uses a virtual frame).

Sorry i can't be help.

This may be a surpise, but wal-mart carries eureka getaway 3500ci packs for under $50, and 2lb 4oz with a single aluminum stay and what appears to be 1/4" padding everywhere. I trimmed mine down to slightly under 2 lbs with all the dumb stuff they put on it. It has no external pockets, but has a lid, and is top, bottom, and rear loadable. It's made of 450D and 900D polyester and has held up well for all of my non UL and winter trips for the past few years. I can't find it on the net anymore, but heres some pics of mine.