There are various crypto's that reward staking by keeping your wallet open and there are crypto's like SIA, MaidSafe, Burst that offer reward for storage capacity. However, I am not aware of any crypto-projects that offer the opportunity to get rewarded through staking traffic? I have plenty of bandwith to offer, which is not used most of the time.

I have frequently been moving around coins in the past months, between exchanges and wallets. Transaction fees can differ a lot I noticed. I also calculated that in some cases it would be more cost efficient to exchange a coin with high transaction fees into a coin with low transaction fees before sending to another exchange (and then change them back).

Is there any overview on (current) transaction fees for let's say the top-100 cryptos?

I had a few bitcoins lending out through Poloniex BTC lending (have been doing this for a while and generated steady growth). However, this morning I noticed that all "My active loans" were suddenly empty and that my overall balance had dropped about 30%.

I downloaded the Lending History, but it did not show anything strange. Only the loans that ended regularly and generated the remaining BTC in balance.

I thought, either somehow those BTC are still active loans, but not showing or I just lost 30% of those coins because a number of lenders were not able to repay?

UPDATE:
Uf, it's sorted out (my stupid error in administration  Embarrassed ). Thanks for the help everybody and sorry for the confusion. It is also a reminder for me that when participating in lending/margin trade it is good to keep a very close eye on in and outgoing transfers. The information that you can gather afterwards is limited. Yet another crypto lesson learnt.

I want to mention that there was NO error of Poloniex or system glitch (what I suspected at first). No blame there.