The "memo" field

[kenCode]

storing a file on the chain is expensive ... storing a hash is not

ok cool, so it is possible then to store a file, that's great news!
1. how expensive and 2. how do we upload the mp3 file?
3. how do we store just the hash?

[xeroc]

I think the only limiting factor is either the max tx size or the max block size ..

Note that for transfers you need to pay a "per kilo byte" fee .. hence storing a file on the chain is expensive ... storing a hash is not

[kenCode]

1. How large is, or can the memo field be?
2. Does it now, or can it (in the near future) support HTML or BBCode for markup?
3a. Would it be possible to also add a BLOB (or similar) field for storing say, mp3 or mp4 6GB+ file(s) with that "memo" textarea?
 3b. or would Storj/Factom technology be needed for this feature?