There are lots of local jobs that might pique your interest that are rarely advertised. You might have to cold call someone, or review your list of contacts to get an in. If it's something you'd enjoy, there's no harm in trying!!

Seasonal Retail

Large box stores and small specialty stores both often need extra help during special seasons like Christmas or Spring Break or Tourist Season.
You might work as a clerk or dress up like The Abominable Snowman... depends on your interest and store needs.
Drop in to your store of choice and ask!

Local Sports Teams

You can get up close and personal with your favourite local sport teams! Jobs include Ushers, Tickets Sales, Janitorial... give their offices a call and find out whether they'll pay for your support.

Teach Your Hobby

Many community centres are interested in expanding their offerings!
You can teach your favourite hobby, skill or interest.
Find out who the Administrator is at your local centre and make an appointment.

Thrift Shop Profits

How often have you found something at a Thrift Shop with the price tag still on it? or in such good condition you wonder if it was ever used.
If you enjoy haunting local thrift stores, scoop these deals and resell them on Craigslist or Kijiji.

Pet Sitters

There are a lot of people who want to take a holiday or need to go out of town... and it's made difficult because of their pets. Others feel guilty leaving their fur babies alone at home all day while they're at work.
If you're a pet lover, you could advertise your services as a pet walker or pet-sitter... and sometimes you get to dictate whether the pet-sitting is done at your home or theirs.

Cultural Pursuits

Ushers at Cultural Centres, Volunteer Coordinators at Music Festivals, Docents at Museums... the list is endless.
You might need to start as a volunteer, however, often the volunteer positions will lead to paid positions.

Courier Services

Drug stores, florists, grocery stores, pizza shops, multi-site businesses... you'd be amazed at how many companies need part-time delivery people. If you love to drive, this is a great gig!

Temp Workers

One often thinks of clerical work when you mention temp workers.
Promotional displays, gardeners, conference/banquet facilities all hire people on an 'as-needed' basis, as opposed to permanent employees.

Other Seasonal

Depending on where you live, there might be other businesses - often government - who use seasonal workers. At the municipal level, maybe a nature sanctuary hires during the Summer and Rec Centres need extra staff during school breaks. Higher levels of government hire people for national parks during the high season. How about local resorts and tourist attractions?

Online Listings

Instead of the usual Help Wanted ads, check out local Craigslist or Kijiji or Used[your city] listings.
There could be interesting jobs listed, or you could post an ad offering your services of choice.
Part-time and Casual gigs are common if you know where to look.