Again, if your blog has a large reader base, then businesses may be interested in paying you to review their services or products. Not only will you get a free trial using whatever these businesses are selling, you will also get a fee for writing them a review and posting it to your site. Paid reviews (and other paid and sponsored content) can be big money, so advertise this service on your contact page to generate business.
Waiting tables and bartending are good ways to make extra money, but it’s not exactly if the work was easy. And if you don’t have any experience good luck applying at the nicest place in town, most restaurants require experience. Also if you have problems dealing with demanding, hungry people – STAY AWAY! The hours are late, sometimes you won’t make any money. Especially right now, starting at new place will be difficult, if you can get hired expect to be the first one cut every night (aka less money) as those with seniority will want to stay. It still is a good deal though. I’ve put myself through college (chem major) without loans, never lived in the dorms, and I have about 10K in the bank. I will continue working in the restaurant biz even after I have a “Real Job,” the extra 10-15K/year for part time work is worth it.
Multi-vendor marketplaces, like ThemeForest, can be very successful. Chose a niche and create a vendor website for it. Your marketplace could be anything, from a platform for local artists to sell their work on, to an online digital product store. Once set up, invite people in that industry to sell their products on your site. You take a percentage of their profits when items sell.