You can learn about SiaFunds here: https://siawiki.tech/wallet/siafund

In summary, it is a second token of the network used to fundraising the project during the IPO (only 100 blocks were premined in Sia, so devs required another income) and encourage the developers to make Sia successful. Their owners receive a proportional part of the 3.9% of fees of each file contract done in Sia. Only 10,000 exist, they are indivisible, and 8800 are owned by the dev team.

You can buy them either at Bisq or in the official Discord chat of Sia using a trusted escrow.

Current price is about 2.5-3BTC/SF

We may want to estimate the profit of renting storage vs electricity cost.

Say that you have a PC with Celeron CPU and 2x 6TB internal hard drives and you leave it running 24/7 just for SIA.
How much is it going to consume ?

Assuming that you rent all your 6 TB at 12-15 $ / month ($2/TB/month) , i am not sure you can cover the energy costs, because it depends on the disk reads/writes operations done in that month, as the disk too consumes power based on I/O activity.

I'd wait for breaking 200 SAT for a confirmation. ATM I'm swing-trading half of it for a short-term profit.

Its on it's way there. Right now, renters that reach 5 Terabytes of uploaded data might see their clients slowing-down or even freezing (lower amounts are ok). For the next update (end of September), the optimizations should be able to allow 40Tb or even more, as the whole database system of renters is being redesigned. Next update is totally focused on the renter side of Sia. There are plans to keep increasing this number in future updates.

Actually this is not a problem of the protocol or the nature of the network, it is just an optimization problem of the reference Client. Either the client of the Core Team or clients of other developers should be able to keep increasing the performance.

I don't know why some people are sp concerned about Cryptopia delisting, the only exchange I can see delist SIA coin that is going to affect the price significantly is Poloniex.

Crytopia says

Moreover: if a host goes offline for a long time or proves he is no longer keeping your data (and no trust is needed here, because hosts need submit proofs of storage to the blockchain), your client will automatically recruit a new host and upload the missing chunks of files to it. And you don't even need to keep that file locally on your computer for this to happen. It is called File Repair.

Why negative feedback? Signature spammers that post the first thing that crosses their mind, traders with their tribulations that can't see every other coin has dropped too because BTC has duplicated its value and that money has to come from somewhere, eventual trolls...

This technology is out there, it is real, it is working, it has very good chances of becoming the standard of online storage...

ASIC mining rig is a great news!