Using a Smart List to pull Leads/contacts who own an asset in Salesforce.com

Can you elaborate a bit more on which "assets" in Salesforce that you are trying to identify? Are you referring to Salesforce Content?

Yes, sorry it is an asset assigned by our Sales team in Salesforce. Basically when a customer purchases a product from us, Sales assigns and asset to the account to keep a record. I'm just hoping there is a way I can access the asset information in Salesforce via Marketo.

Thanks - about the only way for Marketo to see an SFDC Asset associated with an Account/Contact is to add a Lookup field on the Account/Contact record that your users would use to select an appropriate Asset.  The Mareketo lead record would then  have the name of 1 Asset associated with the Account/Contact.  If you have multiple Assets per Account/Contact record, need more than the name of the Asset or don't want your team to have to add the Asset in a field on the Account/Contact record as well as in the related list, then this workaround is not for you. 

I have used this technique with Opportunities to expose the Primary Contact to Marketo and it works great, except the sales team has to enter the primary contact via the lookup field on the Opportunity record as well as in the Contact Role related list.

Thanks. I don't think that will work in ourcase because of the number of assets. I have an idea to gather them into camapings and use that to filter the leads.