Improvisation
Lab equipment can be expensive, but it's not impossible to use certain household items as lab equipment. It's possible to replace many things in the lab, from glassware to entire processes.
Glassware
Boiling chips
Ceramic shards, such as porcelain (unglazed are recommended) can be used as boiling chips.
For better chemical stability, sandpapered glass shards are also better, as they will not react with acids (except hydrofluoric and hot phosphoric acids) and degrade less. It's necessary to sandpaper them, as normal glass is smooth, inadequate for creating a boiling surface. Since glass types are between 5-7 on the Mohs scale, you will need abrasive sandpapers that are higher on the Mohs scale (the black type for example, containing silicon carbide, is good).
Boiling/anti-bumping chips can also be produced from crushed high-quality quartz geodes after being treated with acid. The rough surface of these actually protects against bumping more completely than many lab-grade boiling chips.
Büchner funnel
Coffee filter funnels, usually made of aluminium or stainless steel (rarer), found in certain coffee makers can substitute Büchner funnels very efficiently. They are however unsuited when filtering corrosive substances, such as acidic or alkali solutions (the stainless ones are more resistant to the latter), so they are more suited when filtering organic solutions.
Consumable aluminium beaker
Aluminium cans are more heat-resistant than glass beakers, as they don't tend to shatter on intense heating. The top can easily be removed with a can opener. This is not recommended for use with oxidizing compounds. Large hollow aluminium capacitors can also be used, and since they're thicker than aluminium cans, they deform less when heated. It should be noted, though, that aluminum will react with many acids, sodium hydroxide, and many solutions of metal ions, such as copper(II). Therefore, aluminium beakers are more useful in organic reactions and somewhat useful when dealing with nitric acid. One must be careful when using nitric acid however, since any traces of chloride ions in the presence of acidic protons will dissolve the aluminum. Since aluminum does not have a high melting point, it can melt if overheated.
Distillation kit
A solvent can (like the kinds used to store acetone, methyl ethyl ketone, and n-heptane) can be attached to a metal pipe, bent over into a collecting vessel. These kind of metal retorts are actually preferable to glass for producing and collecting substances such as benzene and phosphorus. The main problem is their tendency to react with products. One may have trouble with the production of metal chlorides, nitrates, or various coordination complexes if the reagents to be distilled react with the apparatus.
Dropper
For most liquids, a drinking straw may be used as a dropper. Placing a finger on the top opening while the bottom end is under the surface of the liquid allows the straw to be lifted from the liquid while retaining the liquid inside the straw.
Filter paper
Coffee filters are sufficient, unless you need smaller size pores. Tea bags are also good and have high wet strength. Air filters can also be used.
Light bulb flask
Carefully cut light bulb glass can be used as a flask, and is quite resistant to heat, though being very thin means it can break very easy and it might not be able to safely contain a stir bar. High pressure sodium bulbs however are much thicker and may be used just like any other piece of glassware.
Scoopulas
One type of tool used in jewelry making and repair resembles a scoopula. It is available at Hobby Lobby for 50 cents. Various spoon-like plastic-ware from ice-cream shops may serve well as replacement scoopulas. Small scoopulas may be made from straws with L-shaped cuts at their ends.
Stirring rods
Glass bead kits often come as glass rods, which can be used out of the box.
Test tubes
Vanilla pods are often sold in glass tubes with a plastic lid. Similar tubes are also found in many bargain stores, as containers for incense sticks. Usually there's two of them, bound with a sticker.
Conveniences
Miscellaneous
Heating elements
Kitchen stoves, portable cooking/camping hotplates, alcohol burners, and even candles can be used for simple reflux setups or dissolving solutes. A metal plate or grate can be placed over a well-controlled fire to obtain very high temperatures, which may however break glass. A sand or an oil bath can be placed on the metal plate. When boiling flammable solvents, avoid using an open flame.
Microwave ovens can also be used for heating chemicals directly and more homogenous.
Water aspirators
For vacuum filtering, Venturi injectors, available at agricultural shops, can effectively replace lab water aspirators.
Video
A significant portion of the ideas came from myst32YT's video of lab tips:
