In a large saute pan, over medium heat, add the oil. When the oil is hot, add the shallots and garlic. Season with salt and pepper. Saute for 1 minute. Add the tomatoes, and saute for 1 minute. Add the mussels and shrimp. Season with salt and pepper. Saute for 2 minutes. Add the wine, bring to a simmer and cover, cook until the shells open, about 4 to 6 minutes. Add the crabmeat and green onions. Season with salt and pepper. Saute for 1 minute. Add the pasta, toss and continue cooking until the pasta is heated through, about 1 minute. Toss the pasta with the cheese and basil. Spoon into the serving dish. Garnish with a drizzle of truffle oil.