Holiday craft fairs usually last a day or two. But at Center City's Center for Emerging Visual Artists, a dozen local artists are exhibiting wares five days a week (and this Saturday), through mid-January. Pick up a framed shadowbox print by Rebecca Gilbert for less than $4. Or, invest in an original framed work for up to $600. Ornaments, pillows, notecards and tote bags are among the snatch-up-ables.