Crypto hand: How far on the river?

[grjr]

Gotta input this manually so bear with me. Also, no reads on BB.

Crypto 1/2 10 players

Hero is MP3 with 4 [img]/images/graemlins/diamond.gif[/img]5 [img]/images/graemlins/diamond.gif[/img]

5 folds, Hero raises, 3 folds, BB calls

(people have been folding to all my good card raises so I have to punish them somehow)

Flop: 3 [img]/images/graemlins/club.gif[/img]8 [img]/images/graemlins/heart.gif[/img]7 [img]/images/graemlins/spade.gif[/img]

BB bets, Hero raises, BB calls

(people have been betting out on the flop against me and I have been blowing them out with aggression)

Turn: 6 [img]/images/graemlins/heart.gif[/img]

BB checks, Hero bets, BB raises, Hero reraises, BB caps

(wow, what does he have?)

River: 5 [img]/images/graemlins/club.gif[/img]

BB bets, Hero???

Ok, 5 on the river isn't a good card for me. BB can't put me on a straight on the turn since I raised preflop. He probably thinks I have a big pair. Could he have 98, T9, a pair of 9's, or something that I beat?

What do you do here? How far would you raise it if BB kept going? Remember, there is no cap on raises on the river at Crypto.