Watch what you're doing with 401(k)s. Most people blindly throw their money in there without looking at what they're doing. You don't want to ever put more into your 401(k) than your company matches. If your company matchs up to 6% (pretty standard), then don't put any more than 6% in there. Anything you want to save beyond that amount needs to be in another type of investment. You should diversify as much as possible. This is true inside of your 401(k) as well. DO NOT put everything in your company's stock, I don't care how well it's doing. Most companies match 401(k) contributions with their own stock, so you'll already have a large portion of your money in that. Beyond that, you should allocate your money across several different types of funds. I'm not going to tell you which ones because there too many different factors to consider. For a quick reference guide, think of it this way: the younger you are, the more risk you should take.
After you reach the limit of what your company matches in your 401(k), you need to look at an IRA. If you qualify for it, go for a Roth. If you don't qualify for a Roth, you should be happy because that means you make TOO much money for one. Go for a traditional IRA instead.
After the IRA, try looking into investing with your life insurance payment. A VUL (variable universal life) policy will cover you like any other insurance policy, but allows you to withdraw that money eventually. Be careful with these though, because once you get into them, you really have to stay with it or you can lose money.
If you STILL have more money to invest, you're one lucky bastard! I would recommend mutual funds after a VUL. Do some research and find a lot of different funds that you like. I personally like index funds and ETFs, you know they're going to do well and don't need to monitor them as much. Again, diversify as much as you can and take as much risk as your age allows.
If you have kids, you may want to look into a 529 plan for their education. These can vary quite a bit from each other, so make sure you look at a few and find what's right for you. Sometimes you can get these through your state, with special incentives to go to a state school.
The last thing I would recommend to anyone is to go with stocks. Much like gambling, most people lose their ass this way. Even bonds are a better way to go, unless you have lots of disposible income.
Enjoy and invest wisely!!!