Edit in JSFiddle

ko.extenders.arrayExtensions = function(target, options) {
    target.filter = function(search, property) {
        return ko.computed(function() {
            var searchValue = ko.unwrap(search);
            var prop = ko.unwrap(property);
            return ko.utils.arrayFilter(this(), function(item) { 
                if (prop) {
                    var itemProp = ko.unwrap(item[prop]);
                    return itemProp.toString().indexOf(searchValue) > -1;
                }
                else {
                    return item.indexOf(searchValue) > -1;
                }
            });
        }, target).extend({ arrayExtensions: true });
    };
    
    target.orderBy = function (propertyName) {
        return ko.computed(function() {
            var propName = ko.unwrap(propertyName);
            if (propName) {
                return this().sort(function(a,b) { 
                    var aProp = ko.unwrap(a[propName]);
                    var bProp = ko.unwrap(b[propName]);
                    return aProp < bProp ? -1 : aProp > bProp ? 1 : 0; });
            }
            else {
                return this().sort();
            }
        }, target).extend({ arrayExtensions: true});
    };
    
    return target;
}

ko.extenders.formatting = function (target, options) {
    if (options === "date") {
        target.date = function(format) {
            return ko.computed(function() {
                return moment(this()).format(format);
            }, target);
        };
    }
    
    if (options === "currency") {
        target.currency = function(symbol) {
            return ko.computed(function() {
                return accounting.formatMoney(this(), ko.unwrap(symbol));
            }, target);
        };
    }
    
    return target;
};

var Dude = function Dude(name, amount, date) {
    this.name = ko.observable(name);
    this.amount = ko.observable(amount).extend({ formatting: "currency" });
    this.date = ko.observable(moment(date)).extend({ formatting: "date" });
};

var viewModel = {
    dudes: ko.observableArray([
        new Dude("hercules", 100, "7/16/2005"),
        new Dude("rembrandt", 2000, "1/1/2013"),
        new Dude("einstein", 666, "9/19/2013"),
        new Dude("einbrandt", 3876, "7/4/1776")
    ]).extend({ arrayExtensions: true }),
    search: ko.observable(""),
    orderBy: ko.observable("name"),
};

ko.applyBindings(viewModel);

Name filter:
<input type="text" data-bind="value: search, valueUpdate: 'afterkeydown'" />
Order by:
<select data-bind="value: orderBy">
    <option value="name">Name</option>
    <option value="amount">Amount</option>
    <option value="date">Date</option>
</select>

<table class="table">
    <thead>
        <tr>
            <th>Name</th>
            <th>Amount</th>
            <th>Date</th>
        </tr>
    </thead>
    <tbody data-bind="foreach: dudes.filter(search, 'name').orderBy(orderBy)">
        <tr>
            <td data-bind="text: name"></td>
            <td data-bind="text: amount.currency()"></td>
            <td data-bind="text: date.date('dddd MMMM Do YYYY')"></td>
        </tr>
    </tbody>
</table>