AppSumo is another SaaS marketplace of sorts where you need to get approved and work with their team on a special "lifetime" membership package or deal. The Pros are that this can provide an influx of upfront cashflow and a lot of buzz and new customers. The downside is you will have to support these customers indefinitely with possibly no additional or recurring revenue, and AppSumo users may be the wrong types of customers, burden your customer support, be vocal online about negative reviews, etc. Take special care to come up with packages that users can get fair value out of but also perhaps give you the option for upsell/cross-sell into additional features or plans later. AppSumo is a different sort of software discovery platform and does not have a free listing option; however it is still mentioning and considering.