Cheap$kate: The best FREE events this weekend in NYC

Canstruction: 21st Annual NYC Competition

Cancan on over to Canstruction at Brookfield Place. OK, you don't really need to cancan, but you should definitely head downtown to see this impressive showing of design and engineering, all created out of -- you guessed it -- cans. The construction competition doubles as a food charity, so even though admission is FREE, bring an unopened can of high-quality food with you to contribute. Donations and sculpture elements go to City Harvest upon dismantling, which occurs Nov. 13. (Opens today, 10 a.m.-6 p.m. daily, FREE, suggested donation of one unopened can of high-quality food per person, Brookfield Place -- Winter Garden, 220 Vesey St. and lobby at 200 Vesey St., brook fieldplaceny .com)

MUSICThe Irrepressibles

Feel like a little music this weekend? Stop by BAMcafé Live tomorrow and Saturday evening to hear the pop melodies of The Irrepressibles, a 10-member, London-based orchestral ensemble led by composer and musician Jamie McDermott. The art-pop group brings elements of cabaret, synth pop and contemporary classical music to their performances, which is sure to make for a good show. (Tomorrow & Saturday, 9 p.m., FREE, BAMCafé Live, Peter Jay Sharp Building, 30 Lafayette Ave., Brooklyn, bam.org)