Tonight's performance of David Schmader's critically acclaimed live commentary on the critically slammed Showgirls is brought to you by local do-gooders Noise for the Needy, a nonprofit that raises money for a new charity each year. Tonight's proceeds go to Urban Rest Stop, which provides free, clean, and safe washing-up facilities for homeless folks. So any bad karma you accrue tonight while ridiculing Elizabeth Berkley's horrific attempts at acting will be canceled out, since the cost of admission goes to a good cause. (Triple Door, 216 Union St, 838-4333. 7:30 pm, $12, all ages.)