There are already a few options for filesharing over the i2p network. These options are gnutella, bittorrent and waste.
For i2p bittorrent, there are several clients. For i2p gnutella, there is just i2phex, so far.
In addition to those options, you can do streaming music and video, and just host files on internal websites.
All of which are anonymous and secure.
More clients are likely to be ported to the network.
Shared content and resources already surpass other simular solutions such as antsp2p. With 1.5 to 2 terabytes of shared content or more.
Transfer speeds are good, with both the network and clients being rapidly developed. I2P is shaping up to be a very nice network for filesharers to hang out and share content.
Anyone looking for a safe place to share content, needs to look no further than i2p and its clients.
Here are a few related links.
i2phex information, downloads and more
A blog with related filesharing news and information